Steven Moffat has said that he believes that this year’s festive special, Last Christmas, is the strangest thing he’s ever written. Which is saying something!

Describing the special in the new issue of the Radio Times he says: “It’s The Thing meets Miracle on 34th Street – the movie we’ve all been waiting for. It’s certainly the strangest bloody thing I’ve ever written.”

But he adds that, despite worries some may have, it’s “actually a scary, tense and claustrophobic adventure,” and “that the very people who think they might hate this, won’t hate it at all. Of all the Christmas specials I’ve done, it’s the one most like the paradigm Doctor Who episode.”

On bringing Santa into the Whoniverse he says: “It does look like the most insane moment when Santa turns up [at the end of Death in Heaven], but we haven’t gone off our rockers. No, Santa is written in properly, in a science fiction way, into Doctor Who.”

Nick Frost also explains that his Santa has “a history with the Doctor,” and “a beef with each other from way back.”