To say farewell to Jodie Whittaker’s Thirteenth Doctor was expected going into the most recent Doctor Who special, The Power of the Doctor. That’s how we knew the final act would include some sort of regeneration. And it did, after a forced regeneration at the hands of the Master (Sacha Dhawan), whose actions then lead to the genuine regeneration when he couldn’t be the Doctor, but it wasn’t what we or the Doctor expected.
The Doctor left Yaz (Mandip Gill) to deal with whatever came after her regeneration alone. (Later, Yaz would join a group with some of the Doctor’s previous traveling companions, where they could open up about their experiences in the TARDIS). Then, she exited the TARDIS and stood alone on a cliff.
It’s the only sad thing. The Doctor asked, “Tell me what happens next.” “All OK. Tag, you’re it, doctor whatever I’m about to be. At that, she transformed into… David Tennant’s Doctor?! Even the Doctor’s clothing was different, with Tennant no longer wearing the suit worn by Whittaker.
It was at this point that Tennant’s Doctor looked down at his hands and clothes and exclaimed in disbelief, “What? What?” His final words on the special were, “What?” as he wiped his face with his hands. (Oh, that was so exciting to hear!)
After Christopher Eccleston’s Ninth Doctor regenerated, David Tennant stepped into the role of the Tenth Doctor for Seasons 2 through 4, and he even underwent a shock regeneration in the season finale owing to a helping hand he’d been keeping around since the Ninth Doctor’s regeneration. After appearances by David Bradley, Colin Baker, Peter Davison, Paul McGann, Sylvester McCoy, and Jo Martin as the Doctor, Tennant made his own comeback (billed as “Introducing David Tennant as the Doctor” in the credits) as a result of the special’s events.
Although Ncuti Gatwa had already been cast as the 14th Doctor and David Tennant had been confirmed to return for the 60th anniversary special as the 10th Doctor’s companion Donna Noble, this regeneration came as a surprise. It has been revealed that Tennant will play the 14th Doctor in three one-off episodes with Tate debuting in November 2023, with Gatwa taking over the role for the next season.
Showrunner Russell T. Davies promised, “If you thought the entrance of David Tennant was a shock, we’ve got plenty more surprises in the way!” Mystery, horror, robots, puppets, peril, and good times await you on the road to Ncuti’s Fifteenth Doctor! Also, how does this factor into the triumphant return of the incomparable Donna Noble? In what ways, and why, are you doing this? We’ll give you a whole year to guess what will happen, and then everything will go to hell.