Who could the villain be in the Doctor Who 2017 Christmas special?

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So who is it? What dastardly creature will bring them together? And what does any of it have to do with World War One, and Mark Gatiss’s army officer?

Well, we may have been granted our first clue during Friday’s Children in Need broadcast, which included a sneak peek at festive special Twice Upon a Time that shed a little light on the threat that binds our errant Time Lords together.

During the scene, Gatiss’s Captain is blown away by his first Tardis experience, pondering whether he’s lost his mind after entering the ship with the two squabbling Doctors.

“Madness?” Capaldi’s Doctor replies.

“Well, you’re an officer from World War One at the South Pole, being pursued by an alien through frozen time. Madness was never this good.”

Now, while this isn’t much to go on, it does give us our first hint at what kind of enemy the Doctors are facing in Twice Upon a Time, and rules out at least one obvious contender – cybernetic humanoids the Cybermen.

The classic Doctor Who baddies WERE already expected to appear in the episode (which partially takes place during their first appearance in 1966’s the Tenth Planet) but it appears they can be ruled out as the main episode villain (while often non-human, Cybermen are not usually described as “aliens”).

Instead, it seems our heroes are dealing with an extra-terrestrial being with the ability to freeze time for their own purposes (assuming that the time freeze is something they're responsible for) and who have designs on the Captain.

So who are the contenders?

Well, a time freeze has cropped up once or twice in Doctor Who’s extended universe of spin-off media, with an alien race called the Vykoids using one in Eleventh Doctor story The Forgotten Army and another (in the form of a time loop) utilised by some vampires in Fifth Doctor novel Goth Opera. Neither of these groups seem particularly likely, to say the least.

Perhaps it’s a better idea to look at groups with a proven history of meddling with time. The Doctor’s own species the Time Lords could be a possibility – though it seems unlikely that Capaldi’s Doctor would refer to them as a singular alien. A rogue Dalek could have the capacity while also meeting the “alien” criteria.

Then again, it could be that some new species or character could create the time freeze – human Torchwood Three member Toshiko Sato managed to fashion a similar “Time Lock” defence in 2008 two-parter The Stolen Earth/Journey’s End, so it’s certainly not technology outside the ability of less advanced civilisations.

But perhaps the most appealing idea is that outgoing showrunner Steven Moffat would pick an antagonist for his final episode closely tied in with his tenure on Doctor Who, which presents a couple of possibilities: creepy regular Matt Smith foes The Silence, who were shown to be capable of time travel, or the iconic Weeping Angels, whose ability of “quantum locking” themselves into stone and sending humans back in time (feeding off their potential energy in their proper timeline) could conceivably be combined, extended and evolved.

(Look, it’s a little far-fetched but this is Doctor Who – if used, it would probably sound very convincing in the finished story).

Why is Mark Gatiss's First World War Captain in the firing line? Well, it depends on the villains – it could be that he plays a pivotal role in World War One, and his death or removal from the timeline (the latter clearly happening in the episode) could present the opportunity to change human history (OR feed off some delicious potential energy – point to the Weeping Angels there).

Alternatively it could be that rumours about his character are true and Gatiss is playing the real-life architect behind the iconic blue police box, Gilbert Mackenzie-Trench (above), who did actually fight in World War One and inadvertently helped design the model for every Doctor’s Tardis exterior since 1963. Who’s to say some confused and disgruntled alien might not have some beef with him over creating the feared symbol of the Doctor?

Then again, it could be that we’ve called this completely wrong and Capaldi’s Doctor was referring to his temporary Tardis team in general (The Captain, Doctor One and Doctor Twelve) as pursued by an alien baddie. And who knows? Maybe the time freezing alien isn’t the main threat of the episode after all, and the explosive scenes on a distant world spotted in the Twice Upon a Time trailer are a sign that an even greater threat awaits our united Doctors.

So alas, despite our best theories all we're left with are a few educated guesses that may or may not pan out in the finished episode. Hopefully the truth will be a Christmas present worth waiting for.

Doctor Who returns to BBC1 this Christmas