How will the Tenth Doctor and Donna Noble return to Doctor Who?

Though we do have a few questions. The last time the Doctor and Donna were together, her mind had to be wiped to save her life (thanks to a load of Time Lord stuff in her brain). If she saw or remembered the Doctor again, she’d die.

Shortly after that, the Doctor regenerated into a new body (played by Matt Smith), and over the years regenerated twice more and finally ended up as the current incarnation Jodie Whittaker.

So…how are they back? The Tenth Doctor is long gone, and Donna can't risk seeing any incarnation. Of course, there are a few possibilities – and returning showrunner Russell T Davies teased pretty much everyone we could think of, which certainly saves us listing them.

How will the Tenth Doctor and Donna Noble return to Doctor Who?

In his own words: “It looks impossible. First, we announce a new Doctor, and then an old Doctor, along with the wonderful Donna, what on earth is happening?

“Maybe this is a missing story. Or a parallel world. Or a dream, or a trick, or a flashback.”

Thanks, Russell! As he suggests, the most obvious explanation for the pair’s return is a “missing story,” as Davies puts it – an adventure the pair shared during their original partnership that we didn’t see in the 2008 series. Thanks to time travel, we could encounter the Doctor and Donna again at a time before they had to part ways, and without retrospectively changing their emotional goodbye.

There’s plenty of precedent for this – Tennant and Tate have actually reprised their Doctor/Donna roles for a “missing story” or two before thanks to some Big Finish audio adventures, and it’s a simple way to bring back old favourites.

Still, there are one or two clues that suggest this isn’t what Davies is planning.

In the announcement release, the BBC highlighted the Doctor and Donna’s farewell, noting the danger of their reunion – why do that if this is just an adventure set in between TV episodes (or, indeed, a flashback?).

“The Doctor and Donna parted ways when the Doctor had to wipe Donna's memory, making her forget him, in order to save her life,” the BBC release says.

“He left her family with a warning: if ever she remembers, she will die. But with the two coming face to face once more, the big question is, just what brings the Doctor and Donna back together?”

If the answer is “it doesn’t matter, because it’s set before that happened,” well…it would just be a bit of an anticlimax. Perhaps we’d be better looking at other theories.

Davies also suggests the idea of this being something to do with a “parallel world” which is certainly possible. Remember, in 2008 (the same episode the Doctor and Donna parted) the Doctor left a half-human clone of himself (it’s complicated, let’s not get into it) in a parallel world. While the main universe Doctor regenerated, it was revealed that this half-human version couldn’t. So who’s to say he’s not still living out in that other world, ready to return to the original universe he grew from?

Perhaps Tennant is playing this ‘other’ Doctor to avoid directly reprising his original role, and perhaps this parallel incarnation will find his way to the main Whoniverse and seek out Donna. After all, his body and her mental injury were created from the same metacrisis – maybe they’re still linked somehow.

This idea sort of lines up, and would require less ripping up of timelines. However, this theory would also require every single viewer to remember incredibly specific plot points from 15 years before, and could be a little inaccessible for a big, showy 60th anniversary special. Somehow, we don’t see Davies going for it.

A dream sequence? Possible! A trick? It’s hard to say what Davies means by this exactly – unless someone is posing as the Doctor and Donna for some reason – but we’re not convinced he’d be able to convince Tennant and Tate to return for a bait-and-switch.

Instead, we might be best looking back at the dark recesses of internet theorising. Some time ago, Tennant’s Doctor Who return was first rumoured accompanied by some strange details. According to some people, Tennant was set to return not as the Tenth Doctor, displaced in time, but as the Fourteenth Doctor, there to replace Jodie Whittaker when she regenerates this autumn.

Somehow, the idea went, the Doctor’s regeneration would see her return to an old body rather than a new one. And while the casting of Ncuti Gatwa would seem to rule out this theory, many fans were quick to notice that the press release about his appointment didn’t include any mention of when exactly this new Doctor would take over the role, whether he’d appear in Jodie Whittaker’s final episode or even whether he was, in fact, the Fourteenth Doctor (after her Thirteenth).

He was billed as a “new Doctor” – and given that at least one half of this bizarre rumour has been proven true with the return of Tennant, who’s to say the rest of it was similarly accurate?

It’s a bit wild, but let’s imagine it’s true. For some reason, Tennant’s Doctor comes back following Whittaker’s regeneration. Confused and alone, he seeks out Donna’s familiar face, but all hell breaks loose…eventually leading to a “proper” regeneration into Ncuti Gatwa.

OK, it’s probably still more likely that we’re getting a flashback, or a multi-Doctor special where Tennant and Tate (from the past) team up with Gatwa to destroy a big ray gun or something.

But if there’s one thing we’ve learned since Russell T Davies decided to come back to Doctor Who with David Tennant, it’s that no fan theory is ever too outlandish to eventually come true…

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