Executive producer and head writer Steven Moffat has talked to Digital Spy and The Big Bang and a bit about the Christmas special, although he couldn’t reveal much. An extract is below, see full interview here.

Episode twelve ended with an almighty trio of cliffhangers. Can you tell us anything at all about episode 13?

”Well, there's going to be some light music and a short note of apology saying, 'The universe ended last week, we're really sorry, we don't know what you're doing here, didn't you get the message?”

Does the series wrap things up with a neat resolve in time for the Christmas special?

"Well we blew up the universe, so it'll be a nice flashback episode at Christmas."

Will there be any kind of trailer for the Christmas special after the episode?

"After the 50 minutes of gentle music and weeping apology? Nope. The universe has ended."

Will you at least reveal the title?

"There will be a Christmas special - well, a flashback Christmas special - but no, we won't be telling you anything, not a single thing. It's too early."

Do you know when we'll find out?

"No, I don't actually know when we'll start releasing that information. I genuinely don't! [We'll] try and work what we've normally done as with all these specials before, but there'll be some strategy that won't be mine."