Who's 'Who'? Peter Capaldi Named the 12th 'Doctor Who' Star

Fall TV

"Doctor Who" fans have been in suspense since Matt Smith announced he was vacating the TARDIS about just who would become the 12th Doctor, and BBC America answered that question in a live broadcast on Sunday: the new Who is Peter Capaldi.

Smith, who announced his plans to leave the series in June, will pass the keys to the TARDIS to Capaldi in the series' 2013 Christmas special, the network revealed Sunday in the live special "Doctor Who Live: The Next Doctor," which aired simultaneously on BBC America, BBC One, Space, and ABC1.

For those asking who the new Who is, Capaldi is best known as the star of the BBC comedy series "The Thick of It" and its 2009 movie spinoff "In the Loop," in which he played government spin doctor Malcolm Tucker. He also starred in the Emmy and Golden Globe-nominated BBC miniseries "The Hour."

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The 55-year-old actor, who has guest starred on "Doctor Who" and the "Who" spinoff series "Torchwood," is also an Oscar winner. In 1995, he won the Academy Award for Best Short Film (Live Action) as the writer and director of "Franz Kafka's It's a Wonderful Life" (which tied for the Oscar with "Trevor").

Capaldi — who played a World Health Organization doctor (i.e. a W.H.O. doctor!) in "World War Z" — is currently filming his role as Cardinal Richelieu in BBC's 10-part remake of "The Musketeers," set to premiere in 2014.

A self-proclaimed lifelong fan of the series, Capaldi said he prepared for the audition by downloading old "Who" scripts and practicing in front of a mirror. On the live special, hostess Zoe Ball provided proof of his fandom: At age 15, Capaldi wrote a letter about "Doctor Who" to the Radio Times TV listings magazine.

"'Doctor Who' belongs to all of us," Capaldi said after being introduced to an audience full of Whovians. "The real reason, the big reason that 'Doctor Who' is still with us is because of every single viewer who ever turned on to watch this show, at any age, at any time in its history, their history, and who took it into their heart."

Capaldi added, via a BBC America press statement, "Being asked to play the Doctor is an amazing privilege. Like the Doctor himself I find myself in a state of utter terror and delight. I can't wait to get started." The actor played Caecilius in the Season 4 "Doctor Who" episode "The Fires of Pompeii."

Smith, who starred as the lovable, bow tie-wearing 11th Doctor since 2010 and was the youngest actor ever to take the role, will begin shooting the "Doctor Who" Christmas special in September, after he finishes filming on the big-screen movie "How to Catch a Monster," the directorial debut of Ryan Gosling. The Christmas special will also be the 800th episode of the venerable British sci-fi show.

"I just want to wish my successor all the best, and good luck, and good on you for getting it, because I know he is both a huge fan of the show, and a nice guy," Smith said during "Doctor Who Live."

"The casting of it made me really excited, genuinely. As a fan, I think it's a really canny choice. I think he'll be a hit. So, good luck, man. It's going to be a thrill."

Meanwhile, the new Who will not be getting a new companion. Jenna Coleman, who stars as Who sidekick Clara Oswald, will continue her role for the show's eighth season, which will air in 2014.

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"I'm so excited Peter Capaldi is the man taking on the challenge of becoming the Twelfth Doctor," Coleman said in a BBC America statement. "With Steven [Moffat's] writing and his talent I know we'll be making an amazing show with an incredible incarnation of number 12. I can't wait to start this new adventure!"

During the special, which included interviews with the fifth Doctor, Peter Davison (whose daughter is married to the tenth Doctor, David Tennant), and celebrity "Who" fans Stephen Hawking and "Dancing With the Stars" judge Bruno Tonioli, "Who" executive producer Stephen Moffat was asked what three words he would use to describe Capaldi.

"Different from Matt," he said.

Capaldi, who had emerged as London oddsmakers' favorite to win the role as Doctor Who, inspired mostly positive Twitter reactions from fans, even though some (like Oscar winner Helen Mirren) had been hoping for the first female Who, or the first African American Who.

Tweeted @tessamatchett:

Said @Splintersunrise:

British actor and comedian Stephen Fry (who starred with Capaldi in an episode of the British dramedy "Fortysomething") seemed to have a problem with the series, but ultimately praised Capaldi, tweeting:

And, in another official thumbs up from the "Who" universe, the sixth Doctor, Colin Baker, tweeted:

And, though he has yet to weigh in via Twitter, we're guessing Capaldi's pal Craig Ferguson will approve of the casting. In a 2009 appearance on "The Late Late Show with Craig Ferguson," Capaldi and the talk show host reminisced about some very un-Who-like behavior: the night they dropped acid together.

Our guide to who's who among Whos: