Spoilers sweeties!!

The BBC announced today (September 2) that Alex Kingston will return to Doctor Who this year. Kingston will reprise her role as River Song in the Christmas special, which began filming this week. Even Kingston was uncertain if she would return to the BBC show, though she did hint at River’s return in interviews earlier this year.

River and the Doctor have a unique relationship, complicated by the fact that they are both time travellers and meet at different points in their own personal timelines. Kingston made her first appearance on the show in a 2008 two-parter where she met the Doctor for the first time (in his timeline) and the last time (in hers). River’s last appearance on the show was in the 2013 episode “The Name of the Doctor”, in which she was seen as a ghost.

The BBC teased River’s return, saying:

It’s Christmas Day in the future and the TARDIS is parked on a snowy village street, covered in icicles, awaiting its next adventure. Time traveller River Song meets her husband’s new incarnation, in the form of Peter Capaldi, for the first time this Christmas.

Showrunner Steven Moffat added:

Another Christmas, another special for Doctor Who – and what could be more special than the return of Alex Kingston as Professor River Song? The last time the Doctor saw her she was a ghost. The first time he met her, she died. So how can he be seeing her again? As ever, with the most complicated relationship in the universe, it’s a matter of time…

This year’s Christmas special will be directed by Douglas Mackinnon, who is also directing this year’s Victorian-themed Sherlock special. Both are scheduled to air on Friday, December 25. Doctor Who’s ninth series will consist of 12 episodes, and will begin airing on Saturday, September 19.