What could a Torchwood/Doctor Who reunion movie actually look like?

• Cyberons, sexy Zygons and Mark Gatiss: the bizarre world of the unofficial Doctor Who spin-offs
• The 7 biggest contradictions in Doctor Who canon
• RadioTimes.com newsletter: get the latest TV and entertainment news direct to your inbox

Since then, Tennant has suggested such a film isn’t overly likely to come about, but the discussion has us wondering – how would a film starring Captain Jack, Rose and the Tenth Doctor even work? When would it be set and what would be the story?

Here's just a few ways they might be able to pull it off.

Make a sequel

The most obvious way to pick up any story – a sequel – could be one of the most challenging in this case, as David Tennant’s Tenth Doctor regenerated quite a long time ago and three new actors have since time-lorded it over the Tardis.

Still, thanks to the Doctor’s habit of jumping around in time there’s no reason we couldn’t get around this. Perhaps the reunion film could catch up with Captain Jack Harkness some time after the events of 2011’s Torchwood: Miracle Day, running into the Tenth Doctor during one of his regular trips to the 21st Century and with some need to get in touch with Rose in the parallel world she went to live in in the 2008 season finale.

The main drawback to this idea is just how awkward and difficult it would be to get all three characters back in the same place, time and universe, which could sap some of the energy from the story – but considering Doctor Who once invented a whole extra Doctor to plug a casting gap in the 50th anniversary special, we’re sure something can be worked out.

Unless of course, we take the lessons of The Day of the Doctor more literally…

Do it in another anniversary special

In just four years we’ll be faced with the 60th anniversary of Doctor Who, and while that’s not QUITE as exciting as the series’ first half-century was in 2013 it’s more than enough of an excuse for one of Who’s iconic multi-Doctor episodes (which usually occur at a significant anniversary).

Billie Piper already made one return (though not quite as Rose) in the Day of the Doctor, so finding an excuse to zap her and Barrowman’s Torchwood team (well, what’s left of it) into a new multi-Doctor story (including Tennant’s Doctor, obviously) doesn’t seem out of the question, even if finding something for everyone to do with even more Time Lords in the mix might be a bit of a struggle.

In which case, a simpler approach could work wonders.

Flashback

Here’s a thought – instead of desperately struggling to force the Tenth Doctor, Rose and Captain Jack together in a sequel, why not jump back to a time when they were all roughly in the same place already?

After all, tie-in novels and Big Finish audio adventures (many of which have starred Tennant, Barrowman and Piper in recent years) have successfully imagined what went on in between onscreen adventures for years, and there’s no reason to suggest a spin-off movie couldn’t plough the same furrow.

Sure, the specific team-up of Tennant, Piper and Barrowman were only onscreen together once – during 2008’s The Stolen Earth/ Journey’s End – but we’re sure some forgotten adventure in or around that time period could just about be slotted in somewhere, if everyone agreed to do some memory wipes afterwards.

The parallel world

Though perhaps that would be a bit too much effort when a ready-made reunion set-up already exists.

Yes, it is awkward that the Doctor has regenerated a few times and Rose is living in another universe – but in that parallel world, a version of David Tennant’s Time Lord (grown from his hand in a regeneration metacrisis) presumably lives on with his former companion, after the real Doctor paired them up in the 2008 season finale.

We can already imagine a storyline where Jack and/or Torchwood accidentally breaks into Rose and the metacrisis Doctor’s domestic bliss (and universe) and needs their help to head back home, while also dealing with the minor differences between their universe and our own, plus any other threats.

With this set up we could have a proper sequel catching up with Rose and Jack as we last saw them AND sidestep the awkward regeneration question, and it’s clear there’s spin-off potential here already. Famously, Russell T Davies once considered setting up a brand new series about Rose joining parallel Torchwood in her new universe before dropping the idea, so maybe he already has a few ideas for how her life would play out.

Added to the fact that the film wouldn't have to worry about Who's main continuity due to its existence in a parallel universe, all these factors make this set-up for a reunion movie all the more convincing.

The only downside would be that technically Tennant wouldn’t be playing the Doctor – this version, while sharing all his memories, absorbed some elements of companion Donna Noble’s personality and was portrayed as slightly more violent than the real Doctor – though we’re sure that it’s a close enough point that nobody would worry too much about it.

Or, alternatively, something completely non-canonical

Look, Doctor Who has a long and proud history of creating weird, tangentially Whoniverse-related spin-off movies and specials (as we’ve written about before) so if all else fails we’re sure we could get Tennant, Barrowman and Piper together for some poorly thought-out, cheap-looking fan service that doesn’t even tie into Doctor Who canon.

Sure, everyone involved are successful actors moving on with their careers, but Doctor Who fans are nothing if not persistent. It may not be today, or tomorrow, or even in the next 10 years, but if enough Whovians keep the dream alive, we’re sure that one day we could see the so-called “golden age” trio back in action for a seriously underwhelming fan project. Clearly, that’d be well worth the wait.

Additional pondering by Thomas Ling

Doctor Who returns to BBC1 in 2020