Michelle Gomez as Missy
She’s been the big bad villain in every Peter Capaldi series to date, and is confirmed to return this series, having played a large part in the trailer. She is the most popular and obvious choice.
It’s very likely that, given her villainous tendencies, the Doctor would want to lock her up and watch over her. Harking back to series three, before John Simm’s Master was shot by Lucy Saxon, David Tennant’s Doctor was planning on taking the Master with him on his travels, watching over him and ensuring he could do no harm. This has a similar feel to how that could have panned out: the Doctor, compassionate as ever, wouldn’t want to harm Missy, but wants to keep her out of harm’s way, and harm out of her way.
John Simm as The Master
Confirmed for a very surprising and very exciting return this series, John Simm’s Master is surely the second most likely to be lurking behind the vault door. Why? For all the same reasons as Missy.
On top of those reasons, some are suggesting that, having not seen the John Simm-Michelle Gomez regeneration, that is what could be in store.
Perhaps (and I’m speculating hugely here), if the Master is dying and the Doctor knows who comes next (Gomez), he’s keeping him alive in the vault, to prevent that regeneration. Given the Gallifreyan symbols on the front, the vault could be slightly more than just a chamber, and perhaps has the ability to keep the Master in his pre-regenerated state.
River Song
We all thought we’d seen the last of Alex Kingston as River Song, but we thought that after her first appearance, and her second, and her third, and so on. Moffat has a soft spot for her, and what with Capaldi’s emotional send-off for her in ‘The Husbands of River Song’, there’s enough of a connection between him and River for another appearance.
And River is a time-traveller, remember, so Kingston could feasibly turn up at any point. It’s provided Moffat with enough stories so far, why not another?
The First Doctor, played by David Bradley
Now then. This is where it gets interesting. It’s a wild fan theory, but I am hugely on board.
Check out Paul Jones’ article in the Radio Times for a more extensive look at why William Hartnell’s Doctor might be returning, as I’ll be keeping it brief.
So, here’s what we know that points towards a potential return for the first Doctor:
- Peter Capaldi has been a huge Who fan since day one, when William Hartnell was the Doctor, and with the return of the Mondasian Cybermen, Moffat is clearly keen to give Capaldi a nostalgic send-off.
- Pearl Mackie’s Bill is named after William ‘Bill’ Hartnell.
- More so than ever this series, the Doctor’s relationship with companion, Bill, is being played up hugely as a grandfather-granddaughter relationship.
- The First Doctor CAN return, despite the passing of William Hartnell, with David Bradley expertly portraying both Hartnell and his Doctor in Mark Gatiss’ fantastic An Adventure In Space And Time.
So, with that in mind, here’s the theory, with a little help from Paul Jones:
The Mondasian Cybermen appeared in just a single Doctor Who TV story, The Tenth Planet. It was the last appearance for William Hartnell, who was by then suffering from ill health and hardly had the energy to deliver his lines, never mind run down corridors being chased by aliens.
Hence, it became one of the first Doctor-light stories, with companions Ben and Polly doing most of the legwork and the Time Lord’s absence explained by the rather dubious idea that he was either lounging around or imprisoned by the Cybermen.
But what if that was just a red herring? What if, during that time, the Doctor had actually hopped into the Tardis and headed off for one final adventure with a later version of himself?
On top of that, remember that scene in the 50th anniversary, The Day Of The Doctor, with Capaldi’s eyebrows? We’re yet to see that take place in Capaldi’s timeline, so could we be about to see that as his time as the Doctor comes to a close? Perhaps, with the first Doctor in tow?
It does seem a bit of a stretch, but we can dream.
Susan, the Doctor's granddaughter
Susan. Her story wasn’t finished.
Peter Capaldi, there, telling a fan who he’d most like to see return to Doctor Who.
[Capaldi] was running around the Tardis saying, ‘She’s got to come back! She’s got to come back!’
Carole Ann Ford, there, the original Susan, telling ‘Doctor Who Magazine’ about Peter Capaldi’s reaction to her visiting the set of Doctor Who.
As mentioned, Moffat does seem keen on giving Capaldi a nice, nostalgic send-off, and with the grandfather-granddaughter relationship blossoming between him and Bill, and the picture of Susan on his desk in his university office, could Susan be in for a return?
So...
So, who do you think is in the vault?
Despite how desperately I’d love it to be the wonderful David Bradley reprising his role as William Hartnell’s Doctor, I can’t see beyond Missy being in the vault. Everything points towards her, or at least John Simm’s Master.
But who knows, maybe the First Doctor or Susan storylines will play out whether they’re in the vault or not.
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