Ncuti Gatwa regenerated into Billie Piper in the series finale of Doctor Who on Saturday night. He left the role after playing the iconic character for two series. Piper, who previously played the Doctor's assistant, Rose Tyler, said the opportunity to "step back on that Tardis one more time was just something I couldn't refuse".

And, of course, the 14th Doctor was played by David Tennant who ended up reuniting with Donna Noble (Catherine Tate) where he continues to live now after Ncuti’s version bi-generated out of him (which could come to play in a later theory…)

Billie Piper will play the next Doctor Who following a dramatic reveal at the end of the latest series. The actress, 42, who previously played Rose Tyler, the sidekick to the ninth and 10th Doctors, played by Christopher Eccleston and David Tennant, will be making her return to the Tardis.