Although fans have no yet seen the final "Doctor Who" Season 9 episodes, the 2015 Christmas Special is already being teased by BBC.

On Tuesday, BBC released the official "Doctor Who" Christmas Special 2015 plot synopsis, along with several promo photos featuring the long-awaited return of River Song.

"It's Christmas Day on a remote human colony and the Doctor is hiding from Christmas Carols and Comedy Antlers," says the synopsis.

"But when a crashed spaceship calls upon the Doctor for help, he finds himself recruited into River Song's squad and hurled into a fast and frantic chase across the galaxy. King Hydroflax (Greg Davies) is furious, and his giant Robot bodyguard is out-of-control and coming for them all! Will Nardole (Matt Lucas) survive? And when will River Song work out who the Doctor is? All will be revealed on a starliner full of galactic super-villains and a destination the Doctor has been avoiding for a very long time."

Given this is the first time Peter Capaldi's iteration of the Doctor is meeting Alex Kingston's River Song, executive producer Steven Moffat says the dynamic will be quite different from Matt Smith's era of "Doctor Who."

"It's strange because they're now, in our human terms, the perfect couple," said Moffat according to Doctor Who TV.

"They're both sexy older people. It's always been slightly strange before with Matt Smith. Now, yeah, they could actually be married. It works. If you're a long term fan of the show you might be interested because there's been a lot of talk about the Doctor and River's glory years but we've never seen them. Here at last we see them as Mr and Mrs Who at the height of their powers. It's great fun."