Doctor Who star Peter Capaldi makes his Doctor debut in less than a fortnight, but how will his past appearances be explained?

Just over a year ago, The Thick Of It‘s Peter Capaldi was officially unveiled as the Twelfth Doctor. Of course, his Doctor debut in Doctor Who‘s fiftieth anniversary special “The Day of the Doctor” a few months later wasn’t his first appearance in the Whoniverse. Capaldi had also appeared as two different characters in series 4’s “The Fires of Pompeii” and Torchwood series 3. No big deal, the fandom says. After all, most of the companions since the reboot have appeared in their show before officially becoming an assistant. And Sixth Doctor Colin Baker appeared as a Gallifreyan guard not long before he was cast.

But this show is run by Steven Moffat, and as we all know, he loves an intricate plot thread. Not long after Capaldi’s unveiling, The Moff stated that previous show runner Russel T Davies had developed a theory on how the same man could have appeared as three different people, and that the idea still worked. The writer stated: “The face is not set from birth. It’s not like he was always going to be one day Peter Capaldi. We know that’s the case because in The War Games he has a choice of faces. So we know it’s not set, so where does he get those faces from? They can’t just be randomly generated because they’ve got lines. They’ve aged. When he turns into Peter he’ll actually have lines on his face. So where did that face come from?”

If Capaldi’s previous performances are going to be a plot thread (however small) in the next series, we can’t help but wonder exactly how they’ll be explained. Of course, we won’t know for sure until the twist is revealed. But what we can do is come up with some outlandish and improbable theories! To get the discussion rolling, we’ve come up with three possible explanations. Check them out below, and let us know what you think!

Note to Self: Save Gallifrey

If this new face is a conscious choice by the Doctor, he could be using it as a way to remind himself of something. After spending hundreds of years on Trenzalore battling all of his fiercest enemies, it’s very possible that the twelfth incarnation of the Time Lord will be a disillusioned old grump. Prone to darkness and melancholy, he may need a reminder of some of his better attributes. By taking the form of Caecilius, he would remind himself of the events of “The Fires of Pompeii” – and crucially, the fact that the Tenth Doctor went back and saved a good family from the erupting volcano (going against the course of history).

This could trigger his memory of saving Gallifrey (and his own incarnation’s presence there) – leading to a nice finale scene where we see him go back and join the other Doctors in transporting their home planet. It would also remind him of the importance of living up to his name and “making people better.” The explanation would be quick, easy, and also address his cameo in “The Day of the Doctor” in a satisfying way, as well as tying into the darker Doctor threads.

Fobwatch

Another possibility is that Caecilius is actually the Twelfth Doctor, under the influence of the Time Lord fob watches we saw the Tenth Doctor and the Master use in series 3. We know that filming for the upcoming run saw the cast travel to Lanzarote, “returning to the scene of an old adventure”. The Spanish island hosts a volcano, so it’s very possible we could see the Twelfth Doctor have to go undercover in Pompeii. This would probably take place before the actual events of the series 4 episode (we doubt David Tennant will be cameo-ing again this soon after his last appearance), allowing a new twist on the original story. Or, the focus of the adventure could be largely on Clara, as she runs around behind the scenes trying to solve a new dilemma.

Wibbly Wobbly Timestreams

Of course, neither of these theories address Capaldi’s Torchwood character. Our third idea is that after entering his time stream in “The Name of the Doctor”, the Time Lord himself became splintered throughout his own life and all of time and space (much like his companion, Clara). However, rather than just his 11th incarnation being scattered – all of them are. The Sixth Doctor gets dispersed as a guard on his home planet, the Fourth Doctor becomes a Curator in the under-gallery, and the Twelfth Doctor splits into two men: one on Pompeii, one in Britain during the events of Children of Earth. These two new creations reflect different sides of the incarnation’s personality: Caecilius is representative of the caring side of Twelve, and John Frobisher is the darkness within him. This would provide a neat way to answer the question featured so prominently in the trailers. Is he a good man? Well, yes – but there’s plenty of shades to his morals in there as well.

Even better, this idea would allow previous Doctors to return in small cameo roles without being tied to the (sometimes) youthful appearances of their original incarnation. With the effect of the time stream meddling with time placement, age, and plenty of other things, the Fourth Doctor can be elderly (as he was in “Day of the Doctor”), and so can others.

How do you think Capaldi’s previous ‘Doctor Who’ appearances will be explained?