Peter Capaldi is the new Doctor. The 12th star of British TV show "Doctor Who" was announced live on the BBC Sunday, ready to replace Matt Smith as the time-travelling hero.

In "Doctor Who Live: The Next Doctor," a half-hour special looking back over the 50-year history of the classic sci-fi show, the actor playing the next Doctor was revealed live on television for the first time. Glaswegian actor Capaldi previously appeared in the episode "The Fires of Pompeii" and "Who" spin-off "Torchwood" but is best known for playing the fabulously sweary Malcolm Tucker in "The Thick of It" and "In The Loop." Previous forays into fantasy include Neil Gaiman's "Neverwhere" and "World War Z," in which he played of all things a W.H.O. Doctor.

Current TARDIS incumbent Matt Smith hands over his sonic screwdriver to the 12th Doctor in a special episode on December 25. "Who" head honcho Stephen Moffatt will then guide the new Doctor and companion Clara, played by Jenna-Louise Coleman, into the eighth series of the show since "Doctor Who" was revived in 2005 with Christopher Eccleston in the lead role. Series 8 is expected to be broadcast in August 2014.

But before then, there's the small matter of a 50th birthday to celebrate. Alongside a drama about the creation of the show, Smith joins forces with previous Doctor David Tennant in a special 50th anniversary episode on 23 November. The special episode, also starring John Hurt, will be broadcast around the world exactly half a century after the show first put kids behind the sofa one momentous Saturday teatime in 1963.

The 50th anniversary will be shown in 3D and in cinemas too.