Jenna-Louise Coleman, Matt Smith

Mimicking Game of Thrones' late, great Ned Stark, the new trailer for Doctor Who's Christmas special warns, "Winter is coming." But this isn't any ol' winter — it's "the last winter of humankind."

So how's the Doctor (Matt Smith) going to get himself out of this doomsday pinch? Well, he'll have the help of his new companion Clara (Jenna-Louise Coleman), of course! Coleman makes her first appearance the Doctor's companion in the special, which debuts on Christmas day.

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Though there are still no hints as to Clara's relation (if any) to her previous Who character Oswin, "The Snowmen" seems so jam-packed full of yuletide action we'll let that mystery slide for now.

Watch the trailer below. Doctor Who: The Snowmen airs Tuesday, Dec. 25 at 9/8c on BBC America.