Is David Tennant's Doctor Who return the work of the Celestial Toymaker?

You see, while it's possible that Tennant is simply reprising his Tenth Doctor – as he did once before in 2013's 50th birthday special The Day of the Doctor – photographs snapped during location filming have seen him wearing a new outfit and not one of the established variations on his suit, tie and sneakers combo.

The leading theory is that, rather than having the Tenth Doctor returning via some out-of-time shenanigans, Tennant is in fact playing the 14th Doctor here – a version almost identical to the Tenth, but not the same – with the actor succeeding Jodie Whittaker in the role before handing over the baton to Gatwa post-60th festivities.

The question that then presents itself is... how is this possible?

In the latest issue of Doctor Who Magazine, Davies himself weighed in, having a bit of fun with the speculation and offering various possibilities as to how Tennant – and Catherine Tate, returning as companion Donna – could be back.

"A mysteriously forgotten excursion for the TARDIS in between Planet of the Ood and The Sontaran Stratagem? Or maybe a multiverse thing; they’re all the rage these days. Maybe this is the Doctor and Donna from Universe 557, all set to collide with our own," he said.

"Then again, maybe, just maybe, this return is so impossible that it’s actually an intricate illusion created by an old enemy of the Doctor’s. Or maybe an old enemy of Donna’s. Nerys!

"Of course, I wouldn’t give that away in the pages of DWM, would I? But then again. This magazine is the first place I ever revealed the name of Billie Piper’s Rose (in issue 340). So read carefully. There are truths in here."

Intriguing... and let's consider what else we know about the 60th anniversary storylines. Fans are convinced that Beep the Meep and the Wrarth Warriors – characters who have previously featured in DWM's own comic strip – will make an appearance, having spotted figures who bear a striking resemblance to these oddball aliens on set. Davies might have even confirmed this in his DWM column, writing that "we’re six days away from a night shoot in Cardiff in which some monsters might be glimpsed. Monsters which might well be familiar to readers of DWM."

It's also been announced that Neil Patrick Harris will play some part in the 60th anniversary, with an official shot of the Emmy-winning actor in character – a Geppetto-esque look, complete with apron and craftsman's tools – as well as photos from Doctor Who location filming in Bristol (which feature a toy shop store front called "Mr Emporium") leading fans to the conclusion that he's portraying the Celestial Toymaker, a sworn enemy of the Doctor who previously appeared in a 1960s TV serial played by Michael Gough.

One more rumour doing the rounds is that the 60th anniversary celebrations will be made up of three specials – and more set snaps, including one of a clapperboard, seemed to confirm that the episode featuring Harris is episode 3. Given everything we know (or at least think we know) so far then, it's not a huge leap to assume that the first episode will be an adaptation of DWM comic strip The Star Beast (which introduced Beep the Meep and the Wrarth Warriors) and that the third will depict a climactic face-off with the Toymaker – with the content of the second special still TBC.

Bringing back an old Doctor and a classic villain in the form of the Toymaker certainly seems an appropriate way to mark an anniversary (on top of whatever additional surprises might remain concealed) – and the return of that particular antagonist might also explain why something seems off with Tennant's Doctor. Russell T Davies seemed to imply that at least one of the theories he put forward in DWM could be genuine, so could it be that "this return is so impossible that it’s actually an intricate illusion created by an old enemy of the Doctor’s"?

As established in his debut appearance some 56 years ago, the Toymaker is an eternal being who possesses near god-like powers to twist reality to his will – it's easy to picture Jodie Whittaker's regeneration in this year's centenary special being somehow hijacked, with an older Tennant emerging an from explosion of golden light to deliver his "What? What?! WHAT?!" catchphrase just before the credits roll...

This new/old Doctor would then embark on a quest to discover exactly what's happened, encountering various alien nasties – and old friends, including Donna – along the way, all building to a final confrontation with the figure responsible, the Toymaker, in the final special. With the threat thwarted, the Doctor's regeneration proceeds unimpeded: enter Ncuti Gatwa.

A wild theory? Perhaps – but like one of the Toymaker's puzzles, the pieces all seem to just about fit.

Doctor Who will return to BBC One later this year – watch episodes now on BBC iPlayer. New release Dr Who and the Daleks is available to buy now in 4K Ultra HD. Daleks - Invasion Earth 2150 AD will be released on 18th July and is available to pre-order now.

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