Peter Capaldi will make his début as the Twelfth Doctor in this year's Doctor Who Christmas special, and begins filming the new series from January. Series 35 (8) will air in autumn 2014.
Doctor Who writer Steven Moffat has revealed that Peter Capaldi "leaps around the place" following his regeneration scene.
The show's 50th anniversary special, 'The Day of the Doctor' aired at the weekend and saw Capaldi briefly appear as the Twelfth Doctor for the first time, but the actor will make his official début in this year's Christmas special.
Moffat told journalists at the Official Doctor Who Celebration in London yesterday: "We've only seen the tiniest moment. It's just the beginning of a process really. Of course, he's brilliant. And just seeing the energy and vitality that he brings to his performance, he works - he's like Matt [Smith] - he works, he's a worker. And he's an extraordinary vital performer."
He added: "The man is not at all elderly in style, he leaps around the place probably more than any other Doctor in that first scene. But that's not how he's gonna play it, he's in a state of post-regeneration madness. It's something we're still working on."
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