Peter Capaldi, the latest incarnation of "Doctor Who," says he is quitting the lead role in the BBC science fiction series at the end of the year.
Capaldi joined the show in 2013. He says "it's been cosmic" but "it's time to move on."
The 58-year-old Scottish actor will star in a 12-episode series starting in April and make his exit in December.
"Doctor Who," first broadcast in 1963, is one of the BBC's most popular programs around the world.
Capaldi is the 12th official incarnation of the Doctor, an alien Time Lord who travels through space and time. The role has been played by 13 actors, including the late John Hurt, who appeared as an alternative Doctor in a single episode.
The Doctor can regenerate into new bodies, and speculation began Tuesday about Capaldi's replacement. Favorites include Ben Whishaw — Q in the 007 films — and comic actor Richard Ayoade.