Inspirations: The Stolen Earth / Journey's End

This story doesn't just bring Series 4 to a conclusion, it draws a line under much of the Russell T Davies era. It also acts as a sequel of sorts to much older stories...

As far as the current season goes, we have explanations for the bees going missing, and for the lost planets. The bees are actually alien in nature and have abandoned the Earth in advance of it being removed from its orbit. Earth has joined the other missing worlds in the Medusa Cascade - brought here by the Daleks.

The Daleks had previously plotted to move the Earth in The Dalek Invasion of Earth. The Doctor mentions having experience of moving planets, and may be referring to this story - but he might also be recalling the roving Mondas (The Tenth Planet).

The Medusa Cascade had previously been mentioned by the Master in Last of the Time Lords. The Doctor had sealed a rift there.

Rose was seen to have returned from "Pete's World", where she had been trapped since the events of Doomsday, in Partners in Crime, and had been glimpsed on TV screens in The Poison Sky and Midnight, before revealing her work with Torchwood to cross the void in Turn Left.

Pompeiian Petrus Dextrus had foreseen her return in The Fires of Pompeii.

Jackie Tyler and Mickey Smith follow Rose to our Earth. They had also been trapped on "Pete's World" at the conclusion of Doomsday. Mickey's grandmother - seen in Rise of the Cybermen - has now passed away. Apparently this was to allow the character to appear in a third series of Torchwood, had it followed a conventional episodic pattern.

The Doctor traced the Earth after a visit to the Shadow Proclamation - an organisation first mentioned in Rose, but referred to in several later stories as some sort of galactic lawmaker.

Working there, as law enforcers, are Judoon, who were introduced in Smith and Jones.

That was Martha Jones' first appearance. She was seen to have joined UNIT in a trio of Torchwood episodes (Reset, Dead Man Walking and A Day in the Death) and in The Sontaran Stratagem / The Poison Sky. 

UNIT still employ the aerial aircraft carrier Valiant, but it is attacked and apparently destroyed by the Daleks here. It first appeared in The Sound of Drums, and was last seen in the Sontaran two-parter.

Dalek Caan is present on the Crucible. It is the last surviving member of the Cult of Skaro - introduced in Army of Ghosts / Doomsday, and last seen in The Daleks in Manhattan / Evolution of the Daleks. It had fled New York via an emergency temporal shift, and we learn that it ended up back in the Time War.

It is locked in a vault with Davros. Sarah Jane Smith recognises his voice before she even sees him, having encountered him on Skaro in Genesis of the Daleks. She had previously met the Daleks on the planet Exxilon in Death to the Daleks.

The Doctor had come back into Sarah's life after the events seen in School Reunion, and the character now had her own spin-off series (The Sarah Jane Adventures). This introduced her adopted son Luke. Mention is made of Clyde and Maria. The latter was to leave the series at the beginning of SJA series 2, whilst Clyde Langer was a regular companion to Luke and Sarah throughout all five series.

K-9 is also seen in Sarah's attic base. She had acquired K-9 Mark III in the spin-off K-9 & Company: A Girl's Best Friend - an event confirmed by its appearance at her home in The Five Doctors.

Davros had survived extermination by his own creations and had been resurrected in Destiny of the Daleks. Imprisoned on Skaro and taken to Earth to stand trial, he had later been freed by the Daleks in Resurrection of the Daleks, but had then been captured and taken back to Skaro for trial in Revelation of the Daleks. On that occasion, he had lost his remaining hand - but in The Stolen Earth we see that he has an artificial one. Davros had later managed to stage a coup on Skaro and become Emperor (Remembrance of the Daleks). He appeared to have sacrificed the remainder of his old body to become the Emperor. It may be that the Daleks brought him back in the form which had successfully beaten their Supreme in order to help them in the Time War, in the same way that the Time Lords had brought Rassilon back in his younger, warrior incarnation.

In this story, the Daleks are once again ruled by a Supreme. This rank of Dalek was first seen in The Dalek Invasion of Earth when it was simply known as the "Black Dalek". The Dalek Supreme is the first red Dalek we have seen outside of the Peter Cushing Aaru movies - despite The Dalek Book claiming that Daleks could not see the colour red.

Like Sarah, Captain Jack Harkness recognises the voice of the Daleks when they intercept their radio messages. He had encountered them in Parting of the Ways when they had exterminated him. Rose, in 'Bad Wolf' form, brought him back to life - inadvertently making him immortal.

Jack is seen with Gwen Cooper and Ianto Jones at the Torchwood Hub in Cardiff. Mention is made to them only recently having lost colleagues Tosh and Owen (killed in the Torchwood Series 2 finale Exit Wounds). 

Torchwood was the first of the new Doctor Who spin-off series, its location in Cardiff deriving from The Unquiet Dead, which had established that a space / time rift ran through the city. Rose recognises Gwen as looking identical to servant girl Gwyneth who she had met in Victorian Cardiff, and the Doctor explains the similarity as a side effect of the rift.

Martha already knows Jack from her Torchwood episodes, as well as from Utopia and The Sound of Drums / Last of the Time Lords.

Then, the Master had obtained from Jack the Doctor's severed hand - which he lost fighting the Sycorax leader in The Christmas Invasion. The Doctor retrieved it after the Master's apparent demise, which is how it came to be back in the TARDIS to become part of the Metacrisis Doctor.

The Metacrisis explains the Ood reference to the Doctor-Donna (Planet of the Ood).

The Doctor and his old companions are brought together on-line by Harriet Jones. You know who she is. First seen as a lowly backbencher in Aliens of London / World War Three, the Doctor knew that she would one day become Prime Minister. He did not realise that he would bring her down, causing her to be forced out of office after she destroyed the retreating Sycorax spaceship (The Christmas Invasion). (By forcing her out, the Doctor inadvertently opened the door for Harold Saxon - the Master - to become the new PM in The Sound of Drums).

She has employed the Subwave Network to contact everyone - technology funded by the Copper Foundation. This was established by Mr Copper - an inhabitant of the planet Sto who had been one of the few survivors from the spaceship Titanic, which almost crashed onto London (Voyage of the Damned). The Doctor had helped him set up home on Earth, with a fortune in local currency.

Finally, Davros taunts the Doctor with reference to all the people who have died trying to help him - allowing for a set of clips from stories covering all four of the RTD series.

Donna's fate - to forget everything which she had learned through contact with the Doctor, so a death of her new personality rather than a physical one - was hinted at by River Song in Silence in the Library, and Dalek Caan, amongst others. She reverts back to the person we first met in The Runaway Bride.

The TARDIS has always had a six-sided control console, and here we see it being operated by half a dozen people. It travels smoothly - as though this is the only way it can work properly. Since 2005, the TARDIS has been seen to travel erratically, throwing its passengers around - despite the fact that it has always had a hexagonal control console, and travelled perfectly smoothly from 1963 - 1989 with just the Doctor at the controls.

Next time, Cyber-steampunk...

Inspirations: Turn Left

Turn Left is this season's Doctor-lite story. The Doctor features briefly at the beginning of the episode, as he and Donna explore an oriental-style market on an alien planet, and then again at the very end as they are reunited after her traumatic experiences of an alternative reality - one in which she never met him, and he died as a result of this.

The episode is therefore able to revisit all the main contemporary Earth stories since The Runaway Bride, and look at what the world might have looked like had the Doctor not intervened. (Naturally the Harold Saxon episodes do not feature - as the Doctor never went to Malcassairo in the altered time-line).

An earlier Doctor-lite story had shown us alternative views of events - Elton Pope's personal experiences of Rose, Aliens in London and The Christmas Invasion in Love & Monsters. Like that story, Turn Left was able to reuse clips from old episodes, as it was supposed to be one of the cheaper episodes.

One of the story arc elements is also cleared up prior to the finale, which is unusual. They are normally saved for the conclusion. Donna was told by Pompeiian auger Petrus Dextrus that she had something on her back, and this proves to be the Time Beetle - the creature which provides us with the alternative time-line view.

It is said to be part of the "Trickster's brigade". This is the being which had featured in The Sarah Jane Adventures - a creature which thrived on chaos and who saw the Doctor and his companions as pivotal characters in maintaining cosmic stability. Remove them from Time, and chaos would ensue.

The changes wrought by the Time Beetle begin even before The Runaway Bride. Donna is on her way to a job interview at H C Clements - where she will meet Lance, who will set her up to be used by the Racnoss, which will ultimately be destroyed by the Doctor after Donna has been transported into his TARDIS - triggering his involvement in events. Donna is talked into going for another job, in the opposite direction to H C Clements - hence the story title.

Instead of being in the Torchwood base under the Thames Barrier, Donna spends that Christmas with friends in a pub nearby - and sees UNIT soldiers removing the Doctor's body. He failed to leave the flooding chamber in time and drowned - because she hadn't been there to urge him to stop his attack on the Racnoss Queen. One of her friends sees something on her back.

Rose Tyler makes her first appearance here. She was stranded in the parallel universe known as "Pete's World" which had its own version of Torchwood, as we know from Doomsday. She is using Torchwood tech to travel across the dimensions to find the Doctor. We have seen her already in "our" universe, in person in Partners in Crime, and on monitors in The Poison Sky and Midnight.

With the Doctor dead, we now start to see alternative versions of some events. 

With the Thames totally drained, London businesses have been badly affected and Donna is made redundant. As she leaves, she sees a TV report about the events of Smith and Jones. The Judoon still take a London hospital to the Moon, but this time it is Sarah Jane Smith and her young companions who are inside. Not only that, but the Judoon return the hospital to Earth too late, and many people die - including the Bannerman Road gang. Martha Jones also dies in this incident.

Donna is then recommended (by Rose) to be outside London next Christmas. They then win a short festive break to the countryside (engineered by Rose). This coincides with the crashing of the spaceship Titanic into the heart of the city (avoided by the Doctor in Voyage of the Damned). Another character - a maid at their hotel - also sees something on her back.

Donna and her family are relocated to Leeds, where they have to share a house with two other families.

Donna refers to a neighbour as "Vera Duckworth" due to her strong Northern accent - a popular plain-speaking character from soap opera Coronation Street.

Hoping for economic help from America, this is halted as that country suffers more than others from the birthing of the Adipose creatures (a comment on the scale of obesity in the US), as seen in Partners in Crime.

Donna later witnesses car engines running rampant due to ATMOS (The Sontaran Stratagem / The Poison Sky). A soldier is the latest person to see something on her back. 

Rose appears and tells her that it is the Torchwood team who were on the Sontaran spaceship when it blew up, with Captain Jack now a prisoner transported to Sontar.

The forcible removal of the other families from their house to a "work camp" reflects the stresses on communities during wartime conditions, when it often turns on its minorities. Wilf recalls events of the Second World War, when the concentration camps were set up in Eastern Europe, as well as the Siberian gulags.

Ironically, Donna calls Mr Colosanto "Mussolini" - the fascist dictator who ruled Italy from 1922 - 1943.

Her next meeting with Rose bears more towards the next couple of episodes, as it is reported that stars are going out.

Rose takes Donna to a UNIT facility where the TARDIS is held. She finally learns the truth about the thing on her back, and of how she can change recent history by stopping herself attending the wrong job interview.

Doctor Who has delivered very few alternative timelines / parallel universes. Of the former, we have only really had Day of the Daleks, and the desolate Earth seen in Pyramids of Mars, whilst the latter have been represented only by the fascist Inferno Earth and "Pete's World".

Whilst the Doctor does not exist in either of the alternative universes, he can exist in alternate time-lines (otherwise he couldn't have died in this version of The Runaway Bride).

Once the Time Beetle has been destroyed, the Doctor hears about the blonde-haired girl whom Donna encountered, and her identity is revealed through the phrase "Bad Wolf" - the story arc from the 2005 series, including an episode of that title. He has previously been informed (by Petrus Dextrus) that "she is returning...".

Things go full circle as, deciding which interview to attend, Donna's mind is made up by a traffic jam - created by her other self being run over.

Production wise, a placeholder title for this episode was "Companion Alone". This was when the companion was to be journalist Penny.

Russell T Davies had often stated that Rose would never be coming back. It would ruin the ending to Doomsday, Billie Piper was far too busy, etc. However, her return at a future point had been planned since before Doomsday was even made.

One major inspiration was the 1998 rom-com Sliding Doors, which showed two alternative versions of a young woman's life - determined by the opening / closing of a tube train door.

The SJA story which first introduced the Trickster was Whatever Happened to Sarah Jane Smith?, written by Gareth Roberts. This showed what happened when Sarah was not around to help save the world, so RTD substituted the Doctor for her in a similarly structured new story.

It was always intended that Penny / Donna would ultimately sacrifice herself in order to correct the time-line, but the BBC had strict guidelines about how they represented suicide in popular dramas.

RTD also had to compare notes with Steven Moffat - who was intending to give Donna an alternative life in his Library story - to avoid repetition.

Next time: a sequel of sorts, not just to another story, but to the last four series - as well as a number of highly regarded classic serials...

Inspirations: Midnight

Midnight is a Companion-Lite story, as opposed to a Doctor-Lite one. 

As we've mentioned before, the production team were getting better at disguising these episodes, where one of the regulars was less available due to filming another episode elsewhere. This one, however, elects not to try to hide things.

The Doctor is specifically taking a trip on his own across a hostile landscape, whilst Donna relaxes in a nearby spa resort.

Catherine Tate was given a substantial role to play in Forest of the Dead - and was going to be almost single-handedly carrying Turn Left. This story was therefore left for David Tennant to fully dominate.

The idea of doing such a "chamber piece" earlier in the series' return would have been unthinkable - potentially off-putting for the casual viewer. However, the programme was now well into its fourth popular series, and Tennant was an established star. There was little risk doing a story at this point with limited cast, confined to a single claustrophobic location. There isn't even a monster as such - something which RTD had insisted upon since 2005.

The production team also wanted to push the boundaries of what sound design could achieve.

According to RTD, Midnight was a response to Voyage of the Damned. As a "disaster movie in space", it had sought to show how people came together and co-operated in the face of adversity. This new episode would show the darker side of human nature - where people turned against each other under stress. Paranoia, violence and fear prevail here.

The story that was to have filled this slot was a Most Haunted POV spoof by Tom McRae, which was originally to have appeared in Series 3. "Century House" was put back to 2008. It would have featured the Doctor with a minimal role for new companion Penny. Realising that McRae's story would need more location filming than at first thought, it was deferred again, and would eventually be dropped all together.

RTD then had to come up with a smaller scale replacement, and he looked to the annoying children's habit of repeating a question whilst ignoring any answer given to them - a bit like "Are we there yet?". This was built upon by having the child copy everything the other person says.

He tested this out on producer Phil Collinson, who quickly found it very irritating. However, he saw how it could form the basis of a scary story if an entity stole your voice - and then your whole identity.

The Doctor could often be very arrogant, always placing himself in charge, and it would make for an interesting story to see him lose this ability.

One inspiration cited by Davies was the Star Trek: TNG episode "Darmok", in which an isolated Captain Picard has to communicate with an alien commander in order that both survive. This was pretty much lifted in its entirety from the movie Hell in the Pacific (1968) which saw lone US and Japanese soldiers stuck on a desert island together in the middle of WWII. That in turn formed the basis of Enemy Mine (1985) - which simply transplanted the action to an alien planet with a crashed human space pilot and one of his adversaries.

The tour bus setting was inspired by the third instalment of the Jeepers Creepers horror franchise, which saw a coach carrying a high school sports team break down in hostile territory. Initially, the monster is mostly heard rather than seen, prowling around the stranded vehicle.

The vehicle was called the Crusader 50, after DWM journalist Benjamin Cook pointed out to RTD that Midnight would be the 50th new story since the return of the series under his watch.

The design was inspired by the SHADO Mobiles from Gerry Anderson's UFO.

As far as the series story arc goes, Hobbes' student Dee Dee has written a paper on the Lost Moon of Poosh. 

Rose Tyler also pops up briefly on the Crusader 50's TV screens, as she had previously on the TARDIS scanner in the earlier Sontaran story.

Professor Hobbes was supposed to have been played by actor Sam Kelly, who was best known as one of the regulars on BBC sitcom 'Allo, 'Allo!. However, he broke his leg just before filming and was replaced late in the day by David Troughton, son of the Second Doctor Patrick Troughton. David had been an extra on The Enemy of the World before gaining the role of Private Moor in The War Games. He had then played the young king in The Curse of Peladon, at a time when he was sharing a flat with future Sixth Doctor Colin Baker.

Dee Dee quotes a poem by Christina Rosetti, wife of the Pre-Raphaelite painter Dante Gabriel Rosetti. Goblin Market was written in 1959, and published three years later.

The "in-flight" entertainment system includes cartoon antics of Betty Boop (created by Max Fleischer in 1930) and a music performance by Italian pop star Rafaella Cara (singing Do It, Do It Again, which was a UK hit for her in 1978).

Inspirations: Silence in the Library / Forest of the Dead

The idea of a story set in a library was an old one for Steven Moffat - one of those he proposed as a follow-up to his 2005 story. Like The Empty Child / The Doctor Dances, it was always intended as a two-parter.

First drafts included the idea of "time windows" which linked every library throughout history - but this idea got used instead in The Girl in the Fireplace for the windows into Reinette's life. His other idea for the library story - creepy angel statues - was also shifted to another story.

Blink had been a Doctor-lite story, and one of the episodes of this Series 4 story would also be Doctor-lite. However, they were getting much better at these "lite" stories, to the extent that the casual audience didn't even notice that there was less of a role for either the Doctor or the companion.

For the 2008 series, the Doctor would take a step back and allow Donna to dominate Forest of the Dead and Turn Left, whilst she would take a back seat for Midnight.

By careful plotting and film scheduling, the Doctor could still play a significant role in the second half of the story, however - unlike his more noticeable absence from Love & Monsters or Blink.

A later version of the story was known as "Space Library" and now included living shadows. Instead of the girl, Cal, there was a little boy watching events on his TV. The library had a robot librarian.

Moffat liked to use childhood fears for his stories, and shadows fitted the bill. Every child could be scared of the shadows in their bedroom at night. In an interview at the time he also mentioned how cracks in walls and lumps under carpets could be scary - both things which he used in later stories, though the carpet was swapped for a bedspread.

The idea of deadly shadows was also a very cheap option for a story that would need a lot of other VFX work.

Moffat's original title for the second episode was "The Doctor Runs", which Russell T Davies hated. It then went under the title "Forest of the Night" for a time.

It was during the scripting period for this story that Moffat was offered the opportunity of taking over from RTD. By creating a figure from the Doctor's future - someone he hasn't met yet - Moffat could set things up for his own tenure if he wanted to develop this relationship further. Some of River Song's story was already in his head. By killing her off in her very first story, he knew he could simply have future stories set in her past - but his future. The crash of the Byzantium is mentioned, as is Darillium, and River knows the Doctor's name - all things which Moffat will return to later.

Moffat wanted to have the Doctor and Donna spending some time exploring the library on their own before anyone else turned up - inspired by the opening episode of The Ark in Space. They needed someone to interact with, however, and so the Nodes were devised. Once he had created them, Moffat then realised he had to have the companion turned into one as the cliff-hanger.

The Nodes were described as having nothing solid behind their faces - "like spoons". Moffat would return to this image for the "Spoonheads" in The Bells of Saint John.

Books mentioned include the works of disgraced Tory peer Jeffrey Archer and the Bridget Jones books.

Monty Python's Big Red Book is also talked about, as is Dan Jones' The Da Vinci Code. In one scene we can see a Clive Barker book on a shelf.

Moffat changed the names of Donna's children to that of his own son and one of his friends. Cal finding hidden buttons on the TV remote was inspired by his son discovering extra buttons under a flap on a similar remote.

There wasn't much of the story arc present, though River is clearly upset when she learns who Donna is - hinting at something terrible in her future.

Forest of the Dead was supposed to be followed immediately by Turn Left, but the producer pointed out that both episodes saw Donna living in an alternate reality. It was therefore decided to place Midnight in between.

The image of a spaceman with a skull face in their helmet is lifted directly from an instalment of the classic cartoon series Scooby-Doo, Where Are You! which launched in 1969. The episode in question was "Spooky Space Kook", which was first broadcast on 20th December 1969. This phantom astronaut haunted an air base and left glowing hand and foot prints - which proved to be phosphorescent paint as he was really a local farmer who was trying to scare his neighbour and the Air Force away in order to buy their land cheaply - and he would have gotten away with too, it if it hadn't been for those meddling kids...

Inspirations: The Unicorn and the Wasp

The Unicorn and the Wasp is this season's celebrity historical. This time it is the 1920's, and a meeting with the "Queen of Crime" Agatha Christie (1890 - 1976).

Like the previous series' celebrity historical - The Shakespeare Code - it is written by Gareth Roberts, and like that story he basically uses the writings of the celebrity to form the basis for his plot. He also employs lots of the celebrity's titles or well known sayings in the dialogue.

In this episode, Roberts uses quite a few of Christie's many, many book titles. These include:

• Sparkling Cyanide
• Dead Man's Folly
• Cat Among The Pigeons
• Nemesis
• The Secret Adversary
• N or M? (The scrap of paper in the fireplace)
• Why Didn't They Ask Evans? (The professor says: "Why didn't they ask... Heavens!")
• They Do It With Mirrors
• Appointment With Death
• Cards on the Table
• Yellow Iris (There is a vase next to the Doctor when he is poisoned)
• Crooked House
• Endless Night
• Taken at the Flood
• The Moving Finger
• Death Comes As The End
• Murder At The Vicarage ("Murder at the vicar's rage..." says the Doctor).

Other book titles are mentioned specifically - Murder on the Orient Express is mentioned by Donna, unaware that Agatha hasn't written it yet. Lady Eddison reads a copy of The Murder of Roger Ackroyd, and it is this which triggers the entire chain of events. 

The Colonel pretending to be disabled, and the jewel thief posing as a house guest, are both plot points lifted from After the Funeral.

The Doctor is The Man in the Brown Suit.

Roberts was inspired to have a giant wasp as the monster in this by the cover of the 1957 Fontana paperback edition of Death in the Clouds. This novel involves a blackmailer being murdered on a flight from Paris to London. An injection of poison has been sued, initially mistaken for a wasp sting. The cover depicts the wasp in close up - making it look like a gigantic insect is threatening the aeroplane:

The Doctor shows Donna a facsimile copy at the end of the episode - one published in the year 5 Billion (suggesting it comes from New Earth).

Some of the incidents are lifted from And Then There Were None. This was previously given a title which is quite unacceptable today. The draft script was going to allude to this:

DONNA: "It's like Ten Little -"

DOCTOR: "Niggles aside..." 

The episode is set in early December 1926 (despite the weather seen on screen) as this was when Christie famously disappeared from her home. Her car was found at Newlands Corner in Surrey, and it was at first feared that she had drowned herself in the Silent Pool - a nearby beauty spot. She was found 11 days later at a spa hotel in Harrogate, claiming loss of memory. She was in the middle of an acrimonious split from her first husband at the time. She elected not to mention the incident at all in her autobiography. Theories include a nervous breakdown, or a deliberate attempt to embarrass her husband. The general public suspected a publicity stunt for her books.

Sherlock Holmes is referenced in that Donna thinks of detectives as going around with a big magnifying glass - an image usually associated with Holmes.

She speaks to Agatha about Miss Marple - not realising that she had not been created yet. Christie's detective in the early years was Hercules Poirot only.

She also gets a bit confused about whether or not Noddy is a real character. Noddy was the 1949 creation of Enid Blyton.

The other big inspiration is the boardgame Cluedo - itself inspired by the works of Christie. In this, the players have to guess the identity of a murderer, as well as the murder weapon used and the location in the country house where the crime took place - e.g. Professor Plum, with the lead pipe, in the library.

This is the very crime seen in the opening section of the episode, as Professor Peach is killed in this fashion, in the same location.

Other characters in the episode also mirror Cluedo characters:

• Robina Redmond = Miss Scarlet
• Clemency Eddison = Mrs Peacock
• Colonel Curbishley = Colonel Mustard
• Miss Chandrakala = Miss White
• Rev. Golightly = Rev. Green

The Doctor has a store of items in the TARDIS catalogued alphabetically, with the paperback novel under "C" for Christie. This also contains the Carrionite crystal ball prison (The Shakespeare Code) and a Cybus Cyberman chest plate.

The Doctor has "kissed" all of his female companions since 2005, and here Donna kisses him as a way of shocking him, to help expel the toxin.

The first idea was to have the story set in the 1960's, with an older Christie acting like her Miss Marple character, before settling on the 1920's which was visually more interesting. 

David Tennant had starred with Fenella Woolgar in a movie about 1920's high society - Bright Young Things, directed by Stephen Fry and based on the work of Evelyn Waugh. Woolgar had form with Christie, having previously featured in two episodes of the ITV series Agatha Christie's Poirot.

Inspirations: The Doctor's Daughter

The story's title is little more than "click-bait" - an on-line headline designed to provoke curiosity. Its sole purpose is to get the casual browser to click on a particular link. This might lead to a genuine item of interest, but more often than not it is a means to artificially boost internet traffic for a site, or it could equally lead to a problem location (adware, malware, spyware or worse).

Here, Russell T Davies simply intends to provoke viewers into thinking they need to see this episode, since it sounds as though something really monumental is going to feature.

It artificially boosts traffic (more people watch), but also leads to a problem location - a fairly rubbish story.

Back in the 1980's, producer JNT employed a similar trick, but his intention was to root out a BBC spy who was leaking details of new episodes to fan groups. He wrote "The Doctor's Wife" on the office planning board, then waited to see who printed the news.

JNT deliberately did not want the story title to get out - or at least hoped it wouldn't, as that would have confirmed his spy fears - so wasn't trying to boost viewership for a change.

The main reason for the title being classed as click-bait is because the Doctor's "daughter" is nothing of the kind. She is simply a clone, bizarrely full-grown. She has some of his biology (two hearts and she can regenerate at least once, though it is very different from the usual Time Lord process where you adopt an entirely new physical and psychological form) but the idea that she can also inherit the Doctor's ideology is a nonsense.

Stephen Greenhorn - the writer - had earlier complained that you couldn't do a story in which the character of the Doctor developed to a great extent. This was when interviewed for his previous episode The Lazarus Experiment. RTD took note of this and told him he could come up with a story which did provoke a change in the Doctor. He has to accept then adapt to Jenny being his offspring. RTD wanted to give David Tennant something to get his teeth into, and also wanted to develop Donna as the Doctor's conscience - teaching him how to be more "human".

Jenny was supposed to stay dead at the end of the episode, but RTD thought the audience would want to see her survive.

One of the key moments in the episode - the Doctor threatening Cobb with a gun - was only a late addition.

Martha Jones comes along with the Doctor and Donna as she was earlier set up at the conclusion of The Poison Sky. She gets separated from the others almost immediately, so one wonders why bother to include her at all. She gets side-lined with the latest "stick an animal head on a man wearing a boiler suit" alien. The Hath are fish people who, for some inexplicable reason, are capable of drowning in water.

The cloning plot is a little too similar to the preceding Sontaran story - another militaristic race.

It is obviously a cheaply budgeted story, with a war being fought by around four soldiers per side.

The gimmick of the war having only been going a couple of days is a twist straight out of The Twilight Zone, or the many many "Weird Stories" anthologies which inspired that series.

In terms of series story arc, the only thing is the running joke of people thinking the Doctor and Donna to be a couple. 

Donna's mobile gets upgraded, as had Rose's and Martha's previously.

The actress selected to play the Doctor's daughter was, of course, a Doctor's daughter. Georgia Moffett's father is Fifth Doctor Peter Davison. She had previously auditioned for the role of society thief "The Unicorn" in The Unicorn and the Wasp, which was filmed earlier. It was claimed that her casting in this was purely coincidental, but no-one believes this.

Inspirations: The Sontaran Stratagem / The Poison Sky

Just to remind: Series 1 would see the return of the Daleks, with the Cybermen held back to Series 2. The Master would be the returning villain for Series 3.

But who to bring back for Series 4?

Back in the mid-1970's, when Target produced its Doctor Who Monster Book, the Ice Warriors were regarded as the bronze medallist monsters, having been seen on screen in four stories - The Ice Warriors, The Seeds of Death, The Curse of Peladon and The Monster of Peladon - and there was no reason to believe they wouldn't be back again soon.

A relatively new alien that had already notched up two appearances in quick succession were the Sontarans, with The Time Warrior and The Sontaran Experiment. By the time the series had come to an end in 1989, they had made two further appearances - in The Invasion of Time and in The Two Doctors.

When it came to considering a returning alien for Series 4, Russell T Davies decided that the Sontarans had more potential - not just dramatic impact, but of comedic value due to their diminutive stature, coupled with their warmongering ways. RTD had recalled the impact of the first ever unmasking reveal - discovering that a Sontaran's head was the same size and shape as its helmet - and he wanted to replicate this image for a new generation of viewers.

As the Judoon had already been designed with black leather uniforms, and large black helmets, a rethink on the costume was planned - with the designers opting for blue instead of the usual black and silver.

Only one classic story had seen a whole squad of Sontarans - The Invasion of Time. There had only been a single Sontaran in their first two stories, and the fourth featured only a pair of the aliens. RTD wanted to see a whole army.

The story sees the return to Doctor Who of Martha Jones. Freema Agyeman had already featured in a trilogy of episodes in Torchwood's third series. This had all been planned from the outset - despite idiotic rumours about her having been sacked after one series on the parent programme.

She spends most of the programme out of action - replaced by a clone copy.

The idea that Sontarans were a clone species did not originate with Robert Holmes, their creator. That Field-Major Styre looked similar to Commander Linx, was mere coincidence - due to the same actor playing both. Styre isn't identical to Linx - he's a different skin colour, with different bone-structure and - more importantly - a different number of fingers. Ironically, Styre is happy to confirm that he is identical to the Sontaran previously encountered by Sarah.

Stor, Stike and Varl look nothing like Linx or Styre, and the number of fingers varies from story to story.

Linx mentioned mass hatchings - which people have taken to imply clone batching, but this is not explicit.

We only see two helmet-less Sontarans in these episodes - and they are not identical. It is only later that we will see that the pair have identical copies - one representing a senior officer class, the other a more junior one.

Their home-world is given as Sontar, which had been established in spin-off media though never mentioned on screen.

The probic vent on the rear of their collar remains a weak point for Sontarans - first established by the Third Doctor in The Time Warrior.

These episodes were the first time that UNIT had featured prominently in the revived series. They had been seen in Aliens of London and been referred to since, but only here do we get to meet individual officers and soldiers, and Martha is now a member - as established in her Torchwood episodes.

Private Jenkins shares a name with the UNIT soldier who was tasked with delivering "five rounds rapid" at Bok in Devil's End, so might well be his offspring. (In the same way that Osgood might well be related to the soldier of that name who we also met in The Daemons).

It had been hoped that Nicholas Courtney might make an appearance, but he was too ill at the time of filming. 

His character is now said to be knighted and on some sort of diplomatic mission to Peru, to explain his absence. In a couple of stories following his appearance in Terror of the Zygons, the Brigadier's absence was explained by him being in Geneva.

The aerial aircraft carrier Valiant makes a return - identified as belonging to UNIT in The Sound of Drums / Last of the Time Lords.

When everyone dons gas-masks, the Doctor asks "Are you my mummy?" - a reference to the gas-masked 'Empty Child' of Series 1.

The Sontaran cordolaine signal mirrors a weapon employed by The War Machines - which disabled gunfire.

General Staal mentions Martha's weak thorax - referencing Linx's similar observation about Sarah Jane Smith.

RTD had contemplated using the name Rattigan for the villain of Partners in Crime - the character who became Miss Foster. He had used the name for the main family in his 1990's soap Revelations.

RTD's original plot for this story involved tampering with the ozone layer. Instead of the ATMOS in cars, the chimneys in people's houses would have a device which the Sontarans interfered with to attack the layer. RTD changed the plan to sat-navs as he thought children would relate to them more than chimneys. Pollution and the environment were, as now, popular concerns.

At one point all the ATMOS workers were going to be clones.

For the second time this series, we get a glimpse of Rose Tyler (on the TARDIS scanner), foreshadowing her return. 

This is the second time Billie Piper, Freema Agyeman and Catherine Tate have all appeared in a single episode, though it is the first time that they feature as the Doctor's trio of companions (Freema having played a different character in Doomsday).

Inspirations: Planet of the Ood

Russell T Davies had always regretted killing all the Ood at the end of The Satan Pit. They were just a passive servant race after all, only aggressive due to a malign outside influence. He determined to revisit the race at a later date and address the servitude issue. It took until the fourth series to get round to this, though there had been a plan to have the spaceship in 42 carrying a cargo of Ood.

As well as a commentary on slavery, the story would also address commercialism in general - including commodification, marketing and advertising.

The industrial exploitation of the Ood would also be a comment on battery farming, as we see them held in pens and containers.

Having the location an ice planet was something RTD wanted, as the series hadn't used this type of environment so far. The Doctor actually comments on it being real snow for a change - a reference to the running joke of snow in the Christmas Specials always being something else.

The story was originally intended to be a two-parter, with a search for the giant Ood brain in a series of ice tunnels taking up considerable time. 

The telepathic Ood would once again be taken over by an external force. Whilst the Ood had been lower down the mix in their first story, they had to be prominent here, so the only other villains would be the human slave-traders. The story would end with the liberation of the Ood.

All of this was handed over to writer Keith Temple to pull together.

Temple and one of the script editors came up with the idea that Ood in their natural state have a second brain which they hold in their hand, to explain why they have to be a non-aggressive race when left to their own devices.

The writer originally intended to make this a partial sequel to The Satan Pit by having Ida Scott feature - come to the Ood-Sphere to investigate the conditions under which the Ood were farmed.

The Ood had originally been inspired by the Sensorites, and this link is made specific as the Doctor states that the Ood-Sphere and the Sense-Sphere are near neighbours in this section of the galaxy.

The "Red-Eye" contagion which affects the Ood was inspired by the zombies in the film 28 Days Later, as well as recent memories of the 2001 Foot and Mouth Disease outbreak.

Popular culture references for the Ood adverts included the silkscreen pop art works of Andy Warhol (multiple copies of a single image in different colours), and the opening credits to Da Ali G Show (different characters exposed by a bright spotlight in a darkened space).

One of the voices customers can purchase for their Ood is that of Homer Simpson ("Doh!") from The Simpsons.

As far as the series' story arc goes, we have the first mention of the Doctor-Donna, which will be explained in Journey's End, and Ood Sigma's declaration that the Doctor's song will soon be ending - which won't be resolved until The End of Time Part II. Donna once again mentions the disappearance of bees.

The Doctor says that revolutions have a habit of starting around him. This could refer to a number of earlier stories (e.g. The Sun Makers, State of Decay, The Happiness Patrol).

Inspirations: The Fires of Pompeii

This story has its origins in the pitch document Russell T Davies prepared for the BBC back in 2003. The eleventh episode of the revived series was to have featured a visit to Pompeii at the time of its destruction by the erupting Mount Vesuvius. In the end, this slot eventually went to a cheaper space-filler instalment - Boom Town (a title that could equally apply here).

It was revived as a possible contender for third episode of the third series. RTD persevered with the story as he wanted one which addressed when the Doctor could, or could not, interfere with History.

The Caecilius family got their names from a common school textbook - the Cambridge Latin Course (1970). This featured a family comprising Lucius Caecilius Iucundus, a banker, his wife Metella and son Quintus.

RTD also claimed to have been inspired by the Asterix the Gaul books.

There are a number of recreated Roman towns around Europe, aimed at tourists, but the production team opted for the Cinecitta Studios on the outskirts of Rome itself. These had been created by Mussolini in the 1930's. The 2004 BBC / HBO series Rome had seen the construction of a huge recreation of ancient Roman streets and squares at the studios, and these were still standing.

This was the first time that the series had seen principal filming overseas since the 1996 TV Movie (set in San Francisco but filmed in Canada). The original series had featured stories filmed in Paris, Amsterdam, Lanzarote and Seville, whilst the Series 3 Dalek story had seen some scene-setting plate shots filmed in New York.

The eruption of Vesuvius which led to the destruction of Pompeii and nearby Herculaneum was fortunately (for us) documented by eye-witnesses - especially Gaius Plinius Caecilius Secundus, better known as Pliny the Younger. He was staying on the Bay of Naples with his uncle, who shared his name and was commander of the Roman fleet in the region. When the eruption struck the elder Pliny decided to mount a rescue mission, an action which cost him his own life - suffocated on a beach by toxic fumes.

The younger Pliny wrote an account of his observations, and his name has since been used to describe a particular volcanic event. A Plinian eruption is an especially explosive one (e.g. that of Mount St Helens in May 1980). Vesuvius had been an explosive event. Plinian eruptions occur where a volcano has been dormant for a very long time, developing a thick rock plug in its crater. Pressure from the magma beneath builds up over time and eventually blasts through in one go, like a cork from a champagne bottle. 

Vesuvius had been so quiet, for so long, that the Romans didn't even realise it was a volcano.

"Volcano Day" was in October 79AD. (For many years it was believed to have occurred in August but archaeological evidence now points to October). Pompeii had previously been rocked by a strong earthquake in 62AD, and rebuilding works were still going on when the volcano destroyed the town.

Caecilius acts as if he has never heard of a volcano before, but Romans would have been very familiar with both Etna and Stromboli on their own doorstep - both of which are in almost constant eruption (even if the name was unfamiliar). It was the explosive eruption of a mountain, with scalding pyroclastic flow, he would have been unfamiliar with.

The monsters of the piece are the Pyroviles - 'pyro-' deriving from the Greek for "fire".

They are designed to look like they are wearing the helmets associated with Roman soldiers.

The human villain is Petrus Dextrus - who just happens to have a stone right arm (petrus = rock, and dextrus = on the right side). 

He is the city's Chief Augur. This was a religious position. The augurs monitored natural signs and interpreted them to foretell future events. They would determine good or bad omens and be used to predict the outcome of, say, a military campaign. Methods used might be the pattern of bird flights, or the study of the entrails of sacrificed animals. Unlike Petrus Dextrus, they were not expected to have inherent powers such as clairvoyance or second sight.

Those who did possess such powers were the Sybils. They were ancient Greek oracles. They were defined by their location (10 of them) and only given names later by Roman writers. The Sybilline Books were bought by the last king of Rome, Tarquinius Superbus. Originally nine books, three were burned by a mysterious old woman to force the king to purchase the remainder. When he refused, another three were burned, and Tarquinius relented and bought the final three. The books were kept in the Temple of Jupiter on the Capitoline Hill, but destroyed in a fire in 83BC. Copies were obtained in 76BC, which survived until the end of the Western Empire around 405AD when they were also burned - this time deliberately by Stilicho, when he thought they were being used to criticise his campaign against the Goths.

The Sybilline Oracles, mentioned in this story, are completely different - being Judeo-Christian texts originating from much later.

The household gods are mentioned - the Doctor and Donna taking over their role for Caecilius' family in the story's epilogue. The gods of the home were the Lares. Lar was originally a god associated with crops and cultivation, worshipped especially where fields met their boundaries. Over time the Lares became a group of gods, personal to the household. Families thought that they helped determine their fortunes. They would be prayed to each evening. Alongside the Lares was Vesta, specifically the goddess of the hearth. She and the Lares were generally worshipped together.

The Doctor refers to the events of The Romans when he and Donna think that they have landed in Rome - stating that the Great Fire wasn't his fault, then equivocating on the matter.

He tells Donna about some of the sights he has seen - suggesting another unseen visit, as he mentions the Colosseum which wasn't built until after the Great Fire.

As far as the series' story arc goes, we have another missing planet (after the Adipose breeding world in the previous episode), but Petrus Dextrus adds the cryptic message that Donna has something on her back, and tells the Doctor that "she is returning" - referring to Rose Tyler.

Inspirations: Partners In Crime

Catherine Tate had enjoyed working on the 2006 Christmas Special - The Runaway Bride - but it wasn't immediately intended that she would return later to become the full-time companion. 

Russell T Davies liked Donna Noble's personality, and initially created a new companion named Penny Carter, who was a journalist. She would have been recently dumped by her boyfriend, and would share many of Donna's characteristics.

Realising that what RTD wanted was a character like Donna, his colleagues simply suggested why not just get Donna. Tate's availability was checked and it was found that she could be free for the Series 4 production dates.

In the meantime, RTD continued to develop Penny's first story. It would be set on contemporary Earth. Penny's mother - Moira - would be a lottery winner, who was also unlucky in love, and her grandfather would have a passion for astronomy. They would hail from the North of England, rather than be yet more native Londoners.

The episode's monster was always intended to be a CGI one. The opening scene would have featured Penny throwing a surprise party for her boyfriend, only to catch him with another woman. Storming off, she would have come across the TARDIS.

When Tate let it be known that she was happy to return as Donna, only a few elements of this first episode (draft title "Second Chances") were retained.

A journalist named Penny was included in Partners in Crime. Donna was unlucky in love, and lived with her mother, who was already established. As she already had a father as well, he was given the astronomy interest.

Bringing back an existing character allowed RTD to skip the introductions. He was able to show how Donna had been influenced by her brief encounter with the Doctor, and was investigating things that might have interested him, which might lead them to meet again. The episode could therefore hit the ground running, with both Doctor and new companion already involved in the main plot.

It would be funny to prolong the meeting - with both characters continually just missing bumping into each other. When the time finally came, it would coincide with the reveal of the main villain and their plan, and would overshadow this.

RTD had by now realised that the best series opener was a lightweight one, with a lot of humour but also some impressive CGI effects.

The sequence with the window cleaner's cradle was one which RTD had hoped to use in earlier episodes. It almost featured in Smith and Jones, and back when he first pitched his vision of the revived series to the BBC he had used this scene as an image, but with the characters being menaced by a Pterodactyl.

For the main plot, the never-ending fad for dieting and weight-loss provided the backdrop. Every month some new diet was promoted, 'guaranteed' by some minor celebrity. Botox injections were a big thing at the time, and RTD thought about there being some alien element hidden in the Botox, which would turn people into mutant creatures. RTD's dislike of cosmetic surgery and peoples' obsession with beauty had already led to the creation of the Lady Cassandra in 2005.

The aliens would be called the Adipose - 'adipose' being bodily tissue which stores fat (not fat itself).

Originally envisaged as looking like the finished version but giant sized, RTD thought it would be funnier to have them as little babies - based on the Pillsbury Doughboy advertising character, a giant version of which had featured in the Ghostbusters film. It was RTD who suggested the inclusion of a single fang - to suggest a more fierce adulthood for the creatures.

This then led to the human villain helping them being a sort of foster mother, so calling herself "Foster". Always intended to be a female figure, she was initially going to be called Rattigan, and she was inspired by Jo Frost, presenter of the Supernanny TV series. (RTD had previously used the name Rattigan for a family in his bizarre ITV soap Revelations, and he would use it this year for a character in the Sontaran story).

Director Peter Jackson had employed a new AI computer programme to animate the vast armies who battle each other in LOTR: The Two Towers. This was called Massive, and allowed figures to act randomly and independently of each other in large crowd scenes.

Miss Foster's demise - temporarily frozen in mid-air before plummeting to the ground - was inspired by Roadrunner cartoons, as it was a situation Wile E Coyote often found himself in. 

The spaceship was deliberately designed to mimic the Mothership from Close Encounters of the Third Kind.

The Doctor uses his "John Smith" alias yet again - first used for him by Jamie in The Wheel In Space, and by the Doctor himself in Spearhead From Space.

To hide her identity, the script referred to the woman whom Donna told about the car keys as "Bin Girl". RTD had quite early on decided to have Rose Tyler make an unexpected appearance in the first episode, with the scene omitted from preview copies to ensure a surprise on broadcast.

Howard Attfield, who played Donna's father Geoff, was ill. It had been known that he had cancer and was undergoing treatment, but it quickly became apparent that his condition was worse than the team were led to believe. He was able to film all of his scenes for this episode - the ones set at night on the allotment with his telescope. Soon after, his condition worsened and it was plain he couldn't carry on. The team had enjoyed working with Bernard Cribbins on Voyage of the Damned and wanted to do more with him. It was decided to invite him to take on the role of Donna's grandfather, Wilf, who would replace Geoff. This would be the same character as the newspaper vendor, who had never been named on screen. Penny Carter's grandfather had originally been an amateur astronomer. The allotment scenes were all re-recorded with Cribbins.

Attfield died soon after filming, and this episode went out with a dedication to him.

Story 199 - The Stolen Earth / Journey's End

In which the Doctor and Donna rush back to Earth, following the news that Rose Tyler has made contact. The Doctor fears that this may signify the breaking of the barriers between universes, which could mean the end of everything. However, all appears to be normal. A few moments later, however, the TARDIS is rocked by some external force. Returning to the doors, they see only space beyond. The ship has not moved, though. The Earth has gone...
Martha Jones is at UNIT's New York HQ when the shift occurs, and she sees that the sky is now full of alien planets. Sarah Jane Smith and her son Luke in Ealing, West London, witness the same phenomenon - as do Wilf Mott and Sylvia Noble in Chiswick, and the Torchwood team in Cardiff. Elsewhere in West London, Rose Tyler has arrived, crossing over from her parallel world.
The Doctor and Donna travel to the headquarters of the Shadow Proclamation to seek help in locating the missing planet. Here, the Shadow Architect informs them that the problem extends beyond the Earth. Other worlds have disappeared as well.
On Earth, a number of spaceships are identified approaching the planet. A message is picked up from them - revealing that they are Dalek ships. The craft begin to attack the planet, targeting military installations.

New York is hit. As UNIT HQ there comes under attack from ground troops, Martha's commander orders her to use Project Indigo to escape. This is a captured Sontaran teleport device. It takes Martha back to her mother's home in London. A communications signal is picked up at Torchwood, and at the homes of Sarah and Martha. Rose, meanwhile rescues Wilf and Sylvia when they are cornered by a Dalek. They had earlier seen many people being taken captive by the Daleks, with those failing to co-operate being exterminated. Rose goes to the Noble home, where they also pick up the communications signal. This is coming from ex-Prime Minister Harriet Jones - a special sub-wave network which had been developed by Mr Copper, whom the Doctor had encountered on the spaceship Titanic. It was designed to seek out everyone connected to the Doctor in the event of a scenario such as this. It allows all the parties to communicate with each other, although Wilf does not have a camera for his computer - so Rose can simply look on.

At the Shadow Proclamation, the Doctor is struggling to understand why these planets have been taken. Donna then reminds him that they have been hearing of other planets which have vanished - such as Pyrovillia. The Doctor adds in the planets which went missing in earlier times, and the assembled group of worlds combine to make a massive energy producing network. Finding them all is still a problem, but once again Donna comes up with the answer when she mentions the fact that bees have been disappearing. The Doctor tells her that many of these are actually extraterrestrial in origin. Sensing some impending catastrophe, they have gone home. Their trail can be followed, however. The Shadow Architect is talking about waging war against whoever is responsible, and wants the Doctor to lead the fight, but he and Donna rush off. The bee trail leads to the Medusa Cascade, but here the trail goes cold.
On Earth, Harriet and the Doctor's friends devise a means of broadcasting a call for his help. Sarah's super-computer Mr Smith will channel a signal to the Doctor's phone through all of the telephones on the planet, via the Torchwood Rift Manipulator. This will give away Harriet's location to the Daleks, so she transfers control over to Captain Jack at the Hub. On a massive space station at the heart of the cluster of planets, the Dalek Supreme orders units to attack the source of the sub-wave network. Harriet is killed. The plan works, however, as the TARDIS picks up the signal. The Doctor discovers that the planets have been hidden in a pocket of time, just out of synch with the rest of the universe.
The ship breaks through and materialises in London.

The Doctor is able to talk with his friends and learn what has been happening. However, someone else breaks into the conversation. The Doctor hopes it is Rose, but he is horrified to find that it is Davros, creator of the Daleks.
As well as the Project Indigo device, Martha had been given an Osterhagen Key. Harriet and Jack had forbidden her to use this, but Martha decides she must follow her commander's orders. She bids her mother goodbye and uses the teleport once again. This time she finds herself in a forest outside a castle in Germany. The custodian also knows of the Key, and tries to stop her using it.
In London, Sarah and Rose have taken to the streets in search of the TARDIS. Jack activates his Vortex manipulator to travel to the city, just as the Daleks locate the new source of the sub-wave network - the Torchwood Hub. Ianto and Gwen prepare for a Dalek attack. One of them overcomes the defences and breaks in.
The Doctor and Donna emerge from the TARDIS and see Rose. As he runs towards her, the Doctor fails to notice a Dalek which shoots him. Jack materialises and destroys it. Close by, Sarah finds herself confronted by a pair of Daleks. Jack, Rose and Donna take the Doctor into the TARDIS, where he begins to regenerate...

The Doctor uses the regeneration energy to heal his injuries, and siphons off the excess into his hand which had been cut off by the Sycorax leader, and which Jack had retained in a special container. Sarah is saved from the Daleks by the sudden arrival of Mickey Smith and Jackie Tyler, who have followed Rose over from the parallel Earth. At the Hub, Ianto and Gwen discover that their late colleague Tosh had set up an extra line of defence - a time lock. The Dalek is frozen in time. It can't get in, but they can't get out. The Dalek Supreme orders the capture of the TARDIS, and it is transported to their space station. This is an artificial planetoid which they call the Crucible. Seeing the TARDIS teleported away, Sarah decides to allow herself to be captured - so Mickey and Jackie follow suit, so they will be taken to where the Doctor and Rose are.
In the Crucible, the Doctor and his companions are forced to leave the ship. Donna lags behind, as she has been troubled by a strange double heart beat sound recently. The ship's doors suddenly lock of their own accord, trapping her inside. The Supreme then orders the destruction of the TARDIS, dropping it into the Crucible's energy core. Donna is drawn towards the disembodied hand, as the ship begins to break up around her. Touching it, she is hit by a blast of regeneration energy. The container smashes, and the hand grows into a duplicate of the Doctor. The TARDIS then dematerialises and reappears elsewhere in the Cascade, but the real Doctor and his friends believe it  - and Donna - destroyed.

Jack tricks the Daleks into exterminating him, so that he can revive after they have removed his body. The Doctor and Rose are taken to a vault where they meet Davros and Dalek Caan, now completely deranged, its casing torn open. It had re-entered the Time War and saved Davros, destroying its sanity in the process. It now has the gift of prophesy, and claims that one of the Doctor's companions will die. Davros tells the Doctor that he has created the ultimate weapon - the Reality Bomb - which breaks down all matter. The stolen planets are needed to generate its power. Elsewhere on the Crucible, Sarah, Mickey and Jackie find themselves about to be used as guinea-pigs to test the weapon. Sarah and Mickey manage to slip away, but Jackie stays to help someone. She has a device which can transport her, and uses it just before the Reality Bomb is used to disintegrate a number of captive humans. Jack joins them, having tracked their technology. Sarah has in her possession a warp star crystal, which harnesses incredible energies. If cracked open, it could destroy the Crucible.
Martha then contacts the Daleks from Germany, and tells them that she will deploy the Osterhagen Key. This operates a chain of nuclear devices buried across the planet - devised to prevent the Earth falling into hostile hands. Sarah and Jack also contact the Supreme and notify it of their weapon.
However, the Daleks simply transport Martha, Jack, Sarah, Mickey and Jackie to the vault, where they are all taken prisoner.

In the TARDIS, the new Doctor tells Donna that he was created partly from her making contact. He is half human, but she is now part Time Lord - a process known as meta-crisis. As Davros begins preparations to activate the Reality Bomb in earnest - which will wipe out all matter beyond the Medusa Cascade - the new Doctor and Donna take the TARDIS to the vault, armed with a device which should be effective against Daleks. Their arrival surprises everyone, not least the Doctor. Davros shoots them both down with electrical bolts from his hand before they can use their weapon. The shock activates the Time Lord half of Donna's new persona, and she starts to sabotage the Dalek systems. She sends them out of control. When the Supreme descends to the vault, Jack shoots it and destroys it, whilst Mickey holds Davros captive. Donna then helps to return the planets to their rightful times and places. The machine which does this then breaks down before the Earth can be returned. Donna and the new Doctor then decide between themselves to end the Dalek threat by self-destructing them - including the one which was threatening the Torchwood team. The Doctor is horrified by this, as it is an act of genocide. He ushers everyone into the TARDIS as the Crucible begins to break up. Davros refuses to go with them, and he curses Caan for not foreseeing this disaster. However, Caan had seen it, but thought that the Daleks did not deserve to survive. It again prophesies the death of one of the Doctor's friends. The TARDIS leaves just as the Crucible explodes.

The Doctor explains to everyone that the TARDIS has six sides to its control console as it should have six pilots. He has everyone operate a different section, then the ship drags the Earth back to its rightful place, using power from the Torchwood Rift Manipulator and from Mr Smith and K9 back at Sarah's home. Francine Jones, Wilf and Sylvia, and Ianto and Gwen find themselves back where they belong. The Doctor drops his friends off. Jack offers Martha a job with Torchwood, which she says she will think about, and Mickey decides to accompany them. There is nothing left for him on the parallel Earth, as his grandmother has now passed away. Sarah goes back home to her son.
The Doctor then takes the TARDIS back to Bad Wolf Bay on the parallel Earth. This is the last time it will ever be able to do so. Rose had wanted to stay with him, but he asks her to look after the new Doctor instead. As he is half human, he only has one heart and won't regenerate. They can grow old together. He reminds her that she once looked after him when he was battle scarred following the Time War, and she must do so again as the new Doctor was also born of war.
Once back in the TARDIS, Donna begins to act strangely. The Doctor tells her that the meta-crisis will kill her, as no human can sustain it. To save her life, he must remove the Time Lord part of her, but this will mean wiping all of her memories of him. She will become the person she was before she ever met him - and this is what Dalek Caan was alluding to. He takes her back to Chiswick and gives her over to the care of Wilf and her mother, warning them that she will die if she ever remembers her recent life. He then departs, travelling on alone once more...

The Stolen Earth / Journey's End was written by Russell T Davies, and was first broadcast on 28th June and 5th July, 2008. It marks the conclusion to Series 4, and the end of Donna Noble's adventures as a regular TARDIS travelling companion. The story is also the first crossover adventure, bringing in characters from The Sarah Jane Adventures and from Torchwood. Sarah is in her attic workroom when the Earth is moved, along with her son Luke (Tommy Knight). Her computer Mr Smith (voiced by Alexander Armstrong) features, and later we see a brief cameo from K9 (voiced as always by John Leeson). Mention is made of their young friends Clyde and Maria being away from London at the time. Captain Jack now only has Gwen Cooper (Eve Myles) and Ianto Jones (Gareth David-Lloyd) as colleagues, following the deaths of Tosh and Owen at the conclusion of Torchwood's second season.
The story doesn't just round off the story arc for the fourth series (with an explanation for the missing planets, vanishing bees and so on), it also acts as conclusion to certain story arc points which have existed since the very first episode of the revived series.
Reference is made to the half-human Doctor being similar to how Rose had first found the Ninth Doctor, bitter and full of rage against the Daleks. We finally get to see the Shadow Proclamation, who were first mentioned in Rose. They use the Judoon (Smith and Jones) as a police force.

All of the Doctor's companions created or employed since RTD took over are seen, as well as their family members. Martha visits her mother Francine (Adjoa Andoh) briefly. Rose encounters Donna's mother Sylvia (Jacqueline King) and her granddad Wilf (Bernard Cribbins). Jackie Tyler (Camille Coduri) isn't content to stay a home like the other parents, but comes along with Mickey (Noel Clarke), packing a huge gun. Only Pete Tyler is really missing from the party - left at home babysitting.
And let's face it, it is a party. This will be the final regular season episode written by RTD. He is about to move on, with only some special episodes planned for what will be David Tennant's last year as the Doctor. The story ends (almost) with everyone gathered round the TARDIS console, followed by a fireworks display. When the end finally does come for RTD, like Peter Jackson with LOTR: The Return of the King, he'll find it difficult to know when to say The End. (ROTK really, really should have closed on the ship sailing off into the Claude-like sunset). We get a foretaste of prolonged endings here as the Doctor has to say goodbye to all of the companions he has amassed through the course of the story.
Another arc ending is that of Dalek Caan of the Cult of Skaro, whom we first met back in Doomsday, which was the last time we visited Bad Wolf Bay as well. The big bad who is brought back from the classic series is Davros, now played excellently by Julian Bleach, who had impressed as the Rainmaker in From Out of the Rain, the series two Torchwood episode. He's first seen lurking in shadow, and only appears fully once he breaks into the sub-wave network - which reminds us that Harriet Jones (Penelope Wilton) also ends her story here. For fans of the classic series, the moment of recognition between Davros and Sarah Jane Smith is one to treasure. She was there on Skaro when the Daleks were first born, and Davros remembers.

In the end, however, this is the story of how Donna Noble died. Catherine Tate has been excellent throughout this season, proving all of the nay-sayers wrong. The ending is truly heartbreaking, and I certainly shed a tear or two along with Wilf - and still do on rewatching this story. Steven Moffat will try the same trick with the Doctor forgetting Clara, but that was nowhere near as effective as Donna's reversion to her old life.
I've pretty much mentioned all the cast who need to be mentioned. The German castellan encountered by Martha is played by Valda Aviks. She was impressed with Nick Briggs' pronunciation for the German speaking Daleks at the readthrough, as seen in the full length DW Confidential for the second episode. The other person to mention is Michael Brandon, who plays General Sanchez of UNIT at their New York offices. He's best known in the UK for the crime drama Dempsey and Makepeace, and for Americans as the narrator of Thomas the Tank Engine (Thomas and Friends in the US).

Overall, it stands up pretty well. There was always a danger that a story containing so many guest characters might fall apart from its own weight, but RTD gets away with it. The main characters get plenty to do, and even the more peripheral ones get their moments. Yes, the TARDIS-towing-the-Earth sequence might be a little sickly sweet for some, but the music saves it. Some fans were unhappy that Rose's return undermined her moving departure at the end of Doomsday, but having her get her very own Doctor to play with does seem the right way to close her story.
Things you might like to know:

• Davros' appearance at first glance seems to go against established continuity (like that ever mattered in this programme). When last seen he had lost most of his body and was encased in a Dalek Emperor shell. The Time War easily reconciles this discrepancy. He has lost his organic hand (seen being shot off in Revelation of the Daleks), and it has been replaced with a metal gauntlet. We'll later see a younger, battle-ready Rassilon, much different from the jovial old bloke seen in The Five Doctors. The Time Lords obviously reincarnated their greatest leader from a time when he was at the peak of his powers. If the Daleks were going to bring back Davros then they would clearly go for the version who went to Skaro a prisoner then single-handedly (no pun intended) overthrew the Supreme Council and set himself up as Emperor - the one who had just lost his last hand and who could now fire energy bolts.
• Terry Molloy, who had played Davros in his last three TV appearances as well as on-going audio performances, was in the running to play the part again - only just missing out to Bleach.
• Had Torchwood gone to a third episodic series, it was planned that Mickey Smith would have joined the team on a regular basis.
• In keeping with the last two season finales, we have a couple of cameo guest appearances. This time we get chat show host, and one time Lily Savage, Paul O'Grady, and Richard Dawkins. Dawkins was married to Lalla Ward at the time (the second incarnation of Romana). It must be said that an evolutionary biologist would not be the obvious first choice to comment on astronomical matters. (But then again, maybe Patrick Moore couldn't make it into a TV studio what with all those Dalek spaceships attacking).
• Ward and Dawkins were very close friends of Douglas Adams (one-time script editor of Doctor Who and responsible for writing one of its greatest ever stories). Whilst it was a current news story at the time of writing these episodes, the disappearance of bees could also be said to be inspired by the departure of the dolphins from the doomed Earth in The Hitchhikers Guide to the Galaxy.
• Some other references to previous stories include one of the missing planets being Clom (from Love & Monsters). Then there is Callufrax Minor (another reference to Douglas Adams, and his story The Pirate Planet).
• The sub-wave network was created by the Mr Copper Foundation - the character played by Clive Swift from Voyage of the Damned.
• The Daleks attack and shoot down the Valiant - UNIT's flying aircraft carrier which was introduced in The Sound of Drums and was more recently seen in this season's Sontaran two-parter.
• Trying to work out who might have moved the Earth, the Doctor mentions that someone tried to do it before. This might be a reference to the Daleks in The Dalek Invasion of Earth, or it might equally refer to the Time Lords doing it (and renaming the planet Ravolox) in the first section of Trial of a Time Lord - the bit also known as The Mysterious Planet.
• A scene which never made it beyond the draft stage saw the Daleks exterminate the Prime Minister - one Aubrey Fairchild. Davies liked the name, and so used it in The Next Doctor.
• And one scene which was filmed, but was cut only after much deliberation (see RTD's The Writer's Tale book) was the throw forward to the Christmas Special, where some Cybermen appeared inside the TARDIS. It's on the DVD box-set.
• Another deleted scene has the Doctor give Rose and his half-human self a piece of coral-like material - with which to grow a new TARDIS.
• The apparent regeneration was withheld from preview copies of the first episode, so came as a huge surprise to everyone, and got people talking for the whole of the following week. Of course, those of us in the know knew that Tennant had already been seen filming scenes for The Next Doctor, so they were never going to spring a surprise new Doctor on us.
• "Osterhagen" also got people speculating - but it is just an anagram of Earths Gone.
• Davies originally intended for the Shadow Proclamation to be made up of various aliens previously seen in the series, including Adipose, Slitheen, Vespiforms, Krillitanes and, would you believe it, a Kroton. As it was, just a few Judoon featured.
• Originally Davies had intended the story to end with Donna hearing the TARDIS dematerialise, with a faint hint of recognition on her features (implying that the new Donna might still exist within her). However, exec-producer Julie Gardner pointed out that children might think that this recognition meant that, as the Doctor had warned, she was going to die.
• German versions of this story don't have the Daleks say "Exterminieren!"They dub the word "Vernichten!" instead - meaning "destroy".
• Right from when he had his hand chopped off in The Christmas Invasion, Davies had always intended that it would return at some point and grow into a second Doctor.