Inspirations: The Pilot

Not to be confused with the unscreened version of An Unearthly Child, which is often referred to as "The Pilot" - but for Steven Moffat it was designed to fulfil the same purpose of allowing people to start watching the series. The term employed was a "soft reset".

This wasn't something new for the series. As well as the obvious relaunches - the 1996 TV Movie and Rose - there were also soft resets with The Tomb of the Cybermen and Spearhead From Space in the classic era, designed to act as jumping-on adventures for new viewers. The Eleventh Hour also sees the series dispense with all associations from the previous RTD era.

The only character already established here, other than the Doctor, is Nardole, who has appeared in the last two Christmas Specials - but knowing who, or what, he is isn't important right now.

Clara has gone, and River Song's story has finally been wound up. You'll recall that Moffat hadn't known he was going to be producing a sixth season - expecting Chris Chibnall to take over with his own new companion, and he had cleared the decks to facilitate this.

Time has moved on for the Doctor and he is now lecturing at a university - something he has been doing for quite some time we learn. There's a big metal vault in the cellars which has something to do with why he is here. There's a Police Box in his rooms, and on his desk are a mug full of sonic screwdrivers, and photographs of his granddaughter Susan and River Song - his first and last to date companions. The desk items are there to please the existing fans and to establish that this is a continuation of a series which began in November 1963, without alienating new viewers.

We find out what this is all about through the eyes of the new companion, Bill Potts, who is the first openly gay companion in the series (Captain Jack slept with anything). She serves in the university canteen but wants to better herself, and the Doctor sees the potential in her - electing to allow her to join his lectures whilst tutoring her privately. She is the agent through which the new viewers get into the series.

This was inspired by a performance of Educating Rita which Moffat had seen in Glasgow. This 1980 Willy Russell play told of the relationship between a working class Liverpudlian hairdresser and her older, boozy college professor, and how each ultimately has a positive impact on the other. It was adapted for the cinema in 1983, starring Michael Caine and Julie Walters.

The plan was to have a funnier companion, straight talking, who would ask the sort of questions which the audience might ask and view things through their eyes. They would also be shown to have watched sci-fi films and TV series, as Moffat had noted that people in Doctor Who rarely acted like they had seen time machines and aliens on screen. For instance, the Doctor tells Bill that the TARDIS has a "cloaking device", just as he had done in the TV Movie - but here he's using language someone who has seen Star Trek would understand.

As well as her sexuality, it was decided that Bill should also be non-white, following criticisms about lack of diversity and representation in Doctor Who and other popular dramas, made by Sir Lenny Henry in a BAFTA speech.

Casting for Bill - a name Moffat heard David Tennant call Billie Piper during production on the 50th Anniversary story - carried a codename. This was "Meantown" - an anagram of 'Woman Ten', as in the female companion for the tenth series. Meantown was also a placeholder title for the story in its earliest form.

Three audition pieces were written, which all found their way into the series in one shape or form. The first was the companion talking about someone she fancied who she serves in the canteen (a boy at this stage). The second was their introduction to the TARDIS interior after escaping from some robots. The companion argued that there was no protection inside a small box made of wood. The third scene was set in a corridor in a Dalek city, where the companion made comments about the monsters' stair-climbing capabilities and kitchen / bathroom appliance design elements.

Once cast, Pearl Mackie wanted to view some old stories but Moffat discouraged this - feeling her lack of knowledge about the series and its tropes would benefit her performance.

The working title for the story became A Star In Her Eye - a reference both to the fact that Bill's would-be girlfriend Heather has an actual star shape in one of her eyes, and to Bill's growing admiration for the Doctor.

The Doctor hangs an "Out of Order" sign on the TARDIS door - just as he did in The War Machines.

The biggest fan-pleasing moment is when the TARDIS arrives in the middle of a Dalek battle. We see that they are fighting the Movellans. The Dalek-Movellan war was first introduced in Destiny of the Daleks, and its outcome formed the background to Resurrection of the Daleks.

Bill was first introduced to the public in a mini-episode titled Friend From The Future, filmed on this futuristic corridor set and featuring a Dalek.

Early in the development of the season, Moffat considered the occupant of the mysterious vault to be either Missy or Davros. Fan speculation was that it might be Susan, after seeing her photograph on the desk - the reasoning behind which was that she had been placed in the vault to protect her from the Time War.

Next time: AI Goes Wrong No.632. Yes, it's the return of one of Mr Moffat's favourite story ideas. The Doctor and Bill visit a beautiful colony planet, but find little to smile about...