The usual secrecy of Doctor Who has many a Whovian racing to guess Season 9's secrets before the September premiere, but barring a few spoilers, sweetie, Christmas has already come. Alex Kingston will return to the role of River Song for the 2015 Doctor Who Christmas special, her first opposite the new Doctor Peter Capaldi.

The BBC announced the return with filming set to begin on the Christmas special this week, though for the most part, mum’s the word on what brings The Doctor and River back together, the synopsis only offering “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.”

The as-yet untitled special will be written by head writer and executive producer, Steven Moffat, produced by Nikki Wilson and directed by Douglas Mackinnon, while Kingston says of the return:

To be honest, I did not know whether River would ever return to the show, but here she is, back with the Doctor for the Christmas special. Steven Moffat is on glittering form, giving us an episode filled with humor and surprise guest castings. I met Peter for the first time at Monday’s read-through, we had a laugh, and I am now excited and ready to start filming with him and the Doctor Who team. Christmas in September?, why not!

Adds Moffat:

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 …

Premiering September 19 with two-part installment “The Magician’s Apprentice” and “The Witch’s Familiar,” Doctor Who Season 9 will feature among its guest stars Game of Thrones favorite Maisie Williams, Rufas Hound, Tom Stourton, Ariyon Bakare, Simon Lipkin, Ian Conningham, Murray McArthur, Barnaby Kay, John Voce, Struan Rodger, Jemma Redgrave, Kelly Hunter, Clare Higgins, Jaye Griffiths, Daniel Hoffmann-Gill, Jami Reid-Quarrell, Aaron Neil, India Ria Amarteifio, Joey Price, Dasharn Anderson, Harki Bhambra, Demi Papaminas, and a returning Michelle Gomez.

In the meantime, we’ve included the first trailers again below, and stay tuned for more on all of Doctor Who’s upcoming season.

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