Peter Capaldi revealed a few secrets to What's On TV about the latest Doctor Who festive special called Last Christmas.
The adventure sees him meet Santa and his elves and get caught up in a deadly mission at a Polar base, which is under attack from creatures called Sleepers and Dream Crabs. There's also a profound event for Clara...
So can you set the scene for this year's festive special, Last Christmas?
"It's a rather clever episode because it's incredibly festive and jolly, but also quite terrifying. I'd say it's one of the scariest Christmas adventures ever. Santa has crashed into Clara Oswald's roof so he's there with his elves, but while this might otherwise be an excuse for cheer and happiness it's actually a nightmarish development, and only the Doctor knows why! So the Doctor has to arrive there, too, to save Clara from what Santa being there means for her life!"
Will Santa survive?! Surely he can't be killed off!
"Kids will be glad to know that Santa will remain intact by the end of the show. He's not a Santa robot or Santa alien or anything sci-fi like that! He's the real genuine Santa Claus!"
The Doctor and Santa Claus have a past history don't they?
"Yes, because the Doctor is slightly competitive with any semi-mythical characters and it's the same with Santa. The Doctor probably thinks Santa's had things to himself for too long."
What was it like working with Nick Frost playing Santa?
"It was just fabulous and he was a brilliant Santa. I'm not an actor who usually suffers much from corpsing, but Nick made me laugh and giggle so much on set. He knows how bad I was getting with him there so he deliberately provoked it in me! There's lots of out-takes of me hiding behind monsters and such like! Nick's great because he brings a great deal of jollity and fun to that role - and he's very convincing as Santa Claus."
Does the Doctor's relationship with Clara change at all in this Christmas special?
"Oh yes. She's fabulous, but yes there's something quite profound that happens to her in this story... but of course I can't go into that."
Michael Troughton stars in this adventure as a scientist on the base that's under attack by Sleepers and Dream Crabs. Was there an inevitable discussion about his dad, Patrick, who played The Doctor from 1966 to 1970.
"Of course, and mainly because I was a huge fan of his dad. In fact, I had his autograph. I wrote a fan letter to his dad, and he sent me a little snapshot of himself on his boat and autographed that with a Biro. I remember really cherishing that because it was such a personal thing. I spoke to Michael a lot about his dad and of course he looks bit like his dad too. Michael and I had worked together before, and he had some very interesting stories."
This is the 10th Doctor Who Christmas special. As an old-school fan does it seem strange to you that the show has become such a big part of Christmas TV tradition now?
"It does, and it has fitted into family traditions too. I've always insisted on watching it. It's terrifying that it's now in that 'Morecambe & Wise' slot as it were. But it just shows how this show has expanded and become so popular among families that it works so well on Christmas Day. It's got that very British mix of something a little scary and something festive. It's like the tradition of having a Christmassy ghost story."
Has your Doctor stopped evolving yet? Is he now how he's always going to be?
"I think it would be wrong to say he's 'arrived' now. And that's certainly not how I feel. That would be lazy, and a bit foolish! I think you have to keep moving him on because in a way if he's regenerated he's still learning about himself, such as how he responds to the universe and the world, so I think he probably will be different again when he comes back for the next series.
So how might The Doctor change in the new series?
"It's inevitable I suppose when you play Doctor Who, that your first season has to be a direct contrast with the previous Doctors. And that's worked well with my age and curmudgeonliness against Matt's youth. I'm just finding out who this character is and also there are more mysteries about him, so it's good to hint at those. There are other things in my Doctor that we're still to display."
*Doctor Who: Last Christmas will be shown on BBC1, Christmas Day at 6.15pm
