What does that Doctor Who cliffhanger mean for the Christmas special?

So the rumours were true. After this week’s multi-Master episode, Peter Capaldi and departing showrunner Steven Moffat will bow out this Christmas with a double-Doctor special, featuring both Capaldi’s Twelfth incarnation and... the First Doctor.

Confirmation came in the final scene of Saturday’s series ten finale in which the Tardis brings the injured Doctor, struggling to resist a regeneration, to an unknown location. Stumbling outside onto the same snowy landscape we had previously seen in a flash-forward at the start of episode 11, the Doctor rails “I will not change!” only to be greeted by the same words echoing back at him: “I will not change. I will not. No, no, no, the whole thing’s ridiculous.”

Approaching through the blizzard, the cloaked, hatted and scarfed figure responds to the Twelfth Doctor’s attempt at an introduction. “The Doctor? Oh, I don’t think so. No, dear me, no. You may be a doctor, but I am the Doctor. The original, you might say.”

You might. While this is the First Doctor, it’s not, of course the original actor to play him. William Hartnell died over 40 years ago but David Bradley seems a worthy replacement, having portrayed both Hartnell himself and his onscreen persona in An Adventure in Space and Time, the BBC drama about the genesis of the series.

You may also recognise Bradley as Hogwarts' straggle-haired caretaker Argus Filch from the Harry Potter films and as the late Walder Frey in Game of Thrones. And this is not his first appearance in actual Doctor Who either – he played ruthless trader Solomon in Eleventh Doctor episode Dinosaurs on a Spaceship.

But what is he doing here? And where is here anyway?

Well we don’t know for sure but my guess would be Earth, at the South Pole, in 1986. This is the scene of the First Doctor’s last stand, in 1966 story The Tenth Planet which, as I’ve pointed out before, gives the perfect opportunity for him to slip away for an off-the-books adventure.

You see, the First Doctor spends much of that story out of action, supposedly confined to a sick room while companions Ben and Polly tackle invaders the Mondasian Cybermen in their first and – prior to series ten – only appearance.

What if, during that time, the Doctor had actually bumped into a later version of himself, jumped into the Tardis and headed off for one last adventure?

Steven Moffat has already shown he has a knack for spotting a blank space in Doctor Who history and creating something to fill it. Arguably the biggest and best idea since the show returned in 2005 is the revelation that there was an unseen regeneration between Paul McGann’s appearance as the Eighth Doctor in the TV movie and Christopher Eccleston’s debut as the Ninth Doctor.

So the idea that the Christmas special will take place during that mysterious period when the Doctor was absent for the majority of his last adventure is both very appealing and very believably Moffat.

But what might this adventure for the two Doctors be? Sure, they could just take the opportunity to catch up on the events of the last two thousand years or so over a cup of tea and one of those macaroons from the Twelfth Doctor’s vending machine, but is that really how either of them would want to spend their last days before they regenerate?

No, they’re much more likely to head off on an important mission and one strong candidate for that is the salvation of Gallifrey. It’s an event that we already know from the Day of the Doctor involves all 12 – sorry, all 13! – Doctors and since we haven’t seen it yet in either of the First or Twelfth Doctor’s timelines, doesn’t that suggest that it’s still to come? And if they both have very little time left, doesn’t that mean that it has to happen, pretty much now?

What a way that would be to wrap up Capaldi’s Doctor Who tenure, coming full circle like that. And what a masterstroke from Steven Moffat – the man who conceived that stirring moment when the Doctors come together to save their home planet – to show it to us first from the point of view of the Tenth, Eleventh and War Doctors and then later from the perspective of two of the others, neatly closing a loop on his own time on the show in the process.

Of course, if it does turn out to be true, that would mean that our first glimpse of the Twelfth Doctor and his attack eyebrows in that unexpected cameo could also be one of our last...

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