Story 5M - Shada

In which the Doctor, Romana and K9 would have visited Cambridge University - responding to a call from the Doctor's old friend and fellow Time Lord, Professor Chronotis...
Sadly, we were never to see this story in its entirety, but can enjoy the scenes that were filmed on DVD, with linking material by Tom Baker and special effects commissioned by John Nathan Turner for the VHS release. Alternatively, you can listen to the Big Finish version which replaces the Fourth Doctor with the Eighth. Or you can read Gareth Roberts' novelisation, based on what there is of the story plus writer Douglas Adams' notes.

The Doctor parks the TARDIS in Professor Chronotis' rooms at St Cedd's College - where he himself once studied for a while. He and Romana go punting on the Cam whilst they await the Professor's return. Meanwhile, on the Think Tank research station in deep space, a scientist named Skagra uses a spherical device to drain the mental energies of his colleagues. He then travels to Earth in a spaceship which lands near the University town, rendering itself invisible. Skagra sets off in search of the Professor also. As he passes them, the Doctor and Romana hear strange whispered voices. A third person seeking Chronotis is his student Chris Parsons, who is looking to borrow a book. The Professor, an extremely eccentric character, allows him to take a few volumes and, after he has left, the Doctor and Romana return. Eventually Chronotis remembers why he asked the Doctor to come here. He borrowed a certain book when he left Gallifrey, and needs the Doctor to return it. The book is "The Worshipful And Ancient Law of Gallifrey", and the Doctor is appalled as he knows that all Gallifreyan books are extremely dangerous in the wrong hands - having unusual properties. The Doctor and Romana search the bookshelves, but cannot find it - as it was earlier borrowed in error by Chris. The Doctor goes off to find him, and Skagra arrives soon after - seeking the book. He uses the mind-draining sphere to attack Chronotis.

Romana had been off looking for milk when Skagra attacked, but she and K9 are able to help maintain Chronotis' basic life functions. He uses his heartbeats, morse-code fashion, to warn them of Skagra and the sphere before dying. The Doctor locates the book which has been studied by Chris and his colleague Clare Keightley. Whilst returning the volume to St Cedd's, he is attacked by Skagra and the sphere - but rescued by Romana. The Doctor, Romana and Chris go to find Skagra's ship, along with K9. They are captured. Skagra takes a copy of the Doctor's mind using the sphere - as Chronotis had failed to tell him what he wanted to know.  Skagra forces Romana to accompany him in the TARDIS to a waiting spaceship, belonging to the brutal Krargs - a crystalline lifeform. The Doctor, Chris and K9 follow in Skagra's ship. Clare turns up at St Cedd's looking for Chris - and meets the Professor, now dressed in his night-shirt and cap. It transpires that these rooms are his disguised TARDIS, and it intervened to save his life. He links with Clare telepathically to help him operate the ship. College porter Wilkins is shocked when he discovers that the rooms have disappeared.
The Doctor and Chris visit the Think Tank and see Skagra's old colleagues - now totally mindless. With K9's help, they beat off an attack by the Krargs.

Skagra's plans are soon revealed. The Gallifreyan book is a key to finding Shada - the Time Lord prison world whose existence is hidden from everyone, including the Time Lords themselves. One of the inmates is a criminal named Salyavin, who possessed incredible mental powers. Skagra wants to steal his mind so that he can use these powers to project his own mind into every sentient being in the Universe.
Everyone reaches Shada where it is found that Salyavin's cell is empty. Chronotis reveals that he is Salyavin. Skagra uses the mind-controlled inmates of the prison to attack the Doctor and his friends. Romana destroys the Krargs and the Doctor builds a device which stops the inmates - as his own mind is mixed in with the controlling force. Skagra seeks refuge on his ship, which promptly imprisons him - having earlier fallen under the Doctor's influence. The inmates are returned to Shada, and the book to the Time Lords. Chronotis' TARDIS returns to Cambridge in time for afternoon tea - to the further consternation of Wilkins.

Douglas Adams' six part adventure should have closed Season 17. As it was, it fell to the underwhelming Horns of Nimon to mark the ending of Graham Williams' tenure as producer, Adams' own tenure as script editor, and to see the departures of Dudley Simpson as "court composer" and David Brierley's interpretation of K9's voice.
What director Pennant Roberts was able to film, before industrial action intervened, were all the location sequences in and around Cambridge as well as the first of the studio blocks. These involved the scenes set in Chronotis' study cum TARDIS, Skagra's spaceship cell, and the Think Tank set - both when Skagra is first seen and later, when it is derelict and the scientists are all wizened old men.
As such, most of the first two episodes are intact, we get to see one sequence involving the Krargs, and Skagra's ultimate fate is also recorded for posterity. Visual effects model shots were also filmed at Ealing.
The location shoot was also affected by industrial action. The entire chase sequence with the Doctor on his bike was planned as a night shoot, and had to be hastily rearranged for daytime when the lighting men downed tools. The studio sessions were cancelled after a union demarcation dispute over the Play School clock - i.e. which union was responsible for operating it.
Several attempts were made to complete the story, but a backlog of high profile light entertainment Christmas Specials made this impossible. The story was officially abandoned in June 1980. 1992 saw the VHS release of the existing material with Tom Baker filling in the gaps - filmed at the Doctor Who exhibit at London's Museum of the Moving Image on the South Bank (sadly no longer in existence). 2013 saw a DVD release.
The punting sequence from the first episode was used in The Five Doctors, once it was known that Tom Baker would not be taking part.
For a fascinating first hand account of the filming of Shada, pick up a copy of Steve Cambden's book The Doctor's Affect (FX Fanzines, 1999).

Cast wise, Christopher Neame portrayed Skagra. He is hampered in the first scenes by the most ridiculously camp silver and white "space-age" costume with big floppy hat. From the little we see, I think he would have gone down as a very good villain, however. A pity they didn't get him back to do something else. Chronotis is Denis Carey, and luckily we get to see a lot of his wonderful performance. A lovely turn as the doddery old Time Lord who turns to steel in later episodes. Being a Douglas Adams script, there is great dialogue throughout, and Carey gets some of the best lines. My favourite is, when told about the strange garbled voices heard by the Doctor and Romana whilst punting: "... Oh, probably undergraduates talking to each other. I'm trying to have it banned." Carey would get another couple of chances on the programme - he is The Keeper of Traken, and the public face of the Borad in Timelash.
Chris Parsons is played by Daniel Hill, who met his wife-to-be on the production (Olivia Bazalgette - production assistant). Clare Keightley is Victoria Burgoyne. This should have been her first big TV role. Wilkins is Gerald Campion - famous for portraying the mischievous schoolboy Billy Bunter on TV in the 1950's.
Episode endings would have been:

1. Skagra is informed by the Krarg commander that his Carrier Ship is prepared...
2. Pursued through the streets by the sphere, the Doctor becomes trapped under a gate...
3. Believing the Doctor and his friends to be already dead, Skagra's ship turns off their oxygen supply...
4. In the Think Tank, K9 is unable to hold back the Krarg any longer, and it lumbers towards the Doctor...
5. The mind-controlled inmates of Shada advance on the Doctor and his friends...
6. Wilkins has brought a policeman to St Cedd's - only to find the missing rooms have returned. The TARDIS dematerialises before their eyes...

Overall, I suspect Shada would have gone down as a good story - maybe a very good one, but I can't quite see greatness in it. The Krargs are a rubbish design, and some of the later unfilmed sequences might have struggled with the FX of the day. Good performances from what we can see, however, and witty dialogue.

Things you would have liked to know:

• The inmates of Shada were to have included some monster cameos - including a Zygon, Dalek and Cyberman.
• Skagra's scientist colleagues on the Think Tank all have names relating to volcanoes - Thira, Akrotiri, Santori, Caldera. Indeed, the same Greek volcano.
• Adams reused elements from Shada in his novel Dirk Gently's Holistic Detective Agency.
• Chronotis' TARDIS is only the third we have seen the interior of in the programme, other than the Doctor's - and the first not to appear to have a central control console (unless it is in the kitchen...). The Monk's and the Master's were invariably redressed versions of the Doctor's. We never got to see any of the other rogue Time Lords' ships up to this point (Omega, Morbius, Drax, War Chief).
• Skagra comes from the planet Dronid - which was once ruled by a schismatic Time Lord President (Morbius?) - hence his knowledge of the Time Lords.
• Chronotis' body disappears when he dies. Up until The Name of the Doctor, this might be what was expected when a Time Lord finally expires - their body as well as their mind totally subsumed to the Matrix back on Gallifrey. Clare's tampering with his ship causes him to be brought back. As he says, by way of an explanation: "Think of me as a paradox in an anomaly, and get on with your tea...".