The new Doctor Who is... David Tennant!

David Tennant is back in the Tardis! To some surprise, Jodie Whittaker's final episode of Doctor Who, titled The Power of the Doctor, saw the Doctor regenerate into the Tenth Doctor – making him now technically also the Fourteenth Doctor. What's particularly perplexing is that Ncuti Gatwa was set to become the next mainline Doctor, and the reason for Tennant's return remains unclear.

The Power of the Doctor brought back many familiar faces from throughout Doctor Who history – including Colin Baker, Paul McGann, and Sophie Aldred. However, with showrunner Russell T. Davies taking over from Chris Chibnall for the upcoming three-episode 60th celebration, some of the biggest returns are still to come. Tennant's comeback has been public knowledge for some time, but no one knew Whittaker would regenerate into him.

"If you thought the appearance of David Tennant was a shock, we’ve got plenty more surprises on the way!" says Davies. "The path to Ncuti’s Fifteenth Doctor is laden with mystery, horror, robots, puppets, danger, and fun! And how is it connected to the return of the wonderful Donna Noble? How, what, why? We’re giving you a year to speculate, and then all hell lets loose!"

Donna Noble was played by Catherine Tate, who is reprising her role for the 60th-anniversary episodes. Unfortunately, we'll have to wait until November 2023 to find out more, while the BBC teases that Gatwa "will then take control of the TARDIS, with his first episode airing over the festive period in 2023." Talk about a mind-bender. For more, check out our list of the best TV shows of all time.