This year's Doctor Who Christmas Special is set to be a cracker (geddit?!?!)!
Katherine Jenkins is starring in the show, alongside Matt Smith, Karen Gillan and Michael Gambon (the actor who plays Dumbledore in the Harry Potter films).
The opera star told the Radio Times that her nerves were "far worse" than normal before the show.
She said: "I just thought I'd love to give it a try'. But I'm the first to say that I really don't consider myself an actress."
It's Katherine Jenkins' first acting role and she is over the moon: "I heard the news that I got the role on my 30th birthday and it was the best birthday present ever."
Lucky Laurence Belcher snatched a role in the Crimbo special.
According to the makers, this episode is a 'clever twist' on the classic tale A Christmas Carol.
Show boss Steven Moffatt revealed: "It's all your favourite Christmas movies at once, in an hour, with monsters. And the Doctor. And a honeymoon."
Matt Smith's second series as Doctor Who will be aired next year.
The finale of the last series saw Amy Pond get married to Rory Williams, played by Arthur Darvill.