'Doctor Who': Steven Moffat Teases Christmas Episode, Says Capaldi's Not Going Anywhere

Much as we’d love to see one, there’s never been a female Time Lord. There’s never really been a Mrs. Who either, and in the absence of both, Alex Kingston’s River Song is as close as you’ll get. A time traveller like the Doctor himself, River Song is a sort of naughtier, less preachy version of the main man, and she’s popped up in a dozen episodes since she was first introduced in 2008. Now she’s back, in an episode that Doctor Who showrunner Steven Moffat says will complete the River story.

“I’m very wary of bringing characters back,” says Moffat, “because I’m always worried that the most exciting thing they do is walk back through the door and then everything else is a bit dull after that. In fact, I had thought we were done with River. But Russell [T Davies, former showrunner] and I email quite a lot about Doctor Who because we’re tragic fanboys. And he was always saying, ‘You can’t not bring her back, because she’s got to be together with [Peter] Capaldi — it will be a sex storm!’”

If that doesn’t sound quite like the fun for the whole family you’d be expecting at Christmas, fear not. The Doctor Who special is Christmassy as eggnog. It begins in a small town in the year 5343 where there is tinsel, fairy lights and the crunch of snow under foot. Then a flying saucer crash lands, the Doctor is summoned, River Song gets out, and a madcap chase ensues, with the Doctor and River being pursued across the galaxy by a very angry nine-foot tall cyborg.

“The running gag,” says Kingston, “is that she doesn’t recognize the Doctor, because of course he’s regenerated since she last saw him. It’s a fast-paced comedy and the interaction between the two is like Spencer Tracy and Katherine Hepburn: it has a screwball quality. What I like about River and the Doctor is they’re equals. River is never somebody who is asking him questions in the way that his companions might.”

Funny that she should mention companions: the season just completed saw the end of Clara (Jenna Coleman), the Doctor’s companion for the last two seasons. Which means there’s a job vacant for next year. Hint, hint… “River for full time companion? I don’t know,” muses Kingston. “The beauty of a character like River Song and what the fans love is she’ll come in for an adventure, and then she goes off again. You can imagine what she does when she’s not with the Doctor. If she were a constant companion I’m not sure whether the fans would enjoy that so much. Why not just bring a new companion in?”

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That’s the question facing Moffat for next year’s tenth season. Naturally, he was tight-lipped about who the new companion might be, saying only that discussions are under way. “There’s nothing easy or automatic about swapping your cast around. You shouldn’t ever get complacent about that.” But he did take the time to quash a couple of rumors that have been rumbling round the Who-niverse. Firstly, on the matter of next year reportedly being only a half series, with Capaldi stepping down midway through: “That’s absolutely not true. Peter’s signed up for the whole of the next series. I can also tell you that the series commission is for a full series. But more critically, the idea of a Doctor regenerating in the middle? I think that’s never going to happen — what actor would agree to coming in half way through a series? You’ve ruined your big night.”

There were also rumors that the casting of a doctor so much older than his companion — Capaldi is 57, his predecessors Matt Smith and David Tennant were both more than 20 years younger — had caused some tension at BBC America. “In America they were very nervous about us making the Doctor older, but the ratings instantly went up over there,” says Moffat. “The age gap to me always seems irrelevant because, first of all, the age gap in terms of the fiction is centuries. And secondly they’re not dating, they’re travelling in time. He’s allowed to be a lot older [than his companion] without it looking dodgy.”

As for Capaldi himself, he says that criticism of his age and casting hasn’t affected him. “I always think that if you’re Doctor Who, somebody somewhere’s going to love you. That’s a comfort. Anyway, every Doctor should be different from the last one. If you want exclusively young sexy guys, to me that’s not Doctor Who.” Capaldi will, he assures us be the Doctor at least for another season, but he would not commit to a fourth year in the role.

“I’m doing next year. Then I don’t know. I love Doctor Who, but it can be quite an insular world and I do want to do other things. There will come a time when this is over. But I knew that when I started. That’s the thing with the Doctor —even when you accept the job you know there’ll come a day, inevitably, when you’ll be saying goodbye.”

The Doctor Who Christmas Special airs December 25 on BBC America.