'Doctor Who' Christmas Special Reminder Promo Released

The Doctor Who Christmas Special will air tonight on BBC1 and BBC America and the cast has released a promotional video wishing fans a happy Christmas.

The video begins with a Mondasian Cyberman letting fans know that "Christmas will be upgraded" followed by a Dalek demanding that viewers "CELEBRATE!" Then the human cast gets into the mix.

"I'd like to wish you all a Merry Christmas and a happy new year," says David Bradley, who will debut as the First Doctor in "Twice Upon a Time."

"Hello all Doctor Who fans, since this is my very last chance to say so, Merry Christmas and a happy new year to you all," says outgoing Doctor Who showrunner Steven Moffat.

"Happy Christmas 2017," says Pearl Mackie, who will play companion Bill Potts for the last time in tonight's Christmas Special. "Happy new year. All of those things. Deck the halls, boughs of holly. I love Christmas."

"A very merry Christmas to all of you at home," says guest star, Mark Gatiss.

"Hello, this is Nardole from Darillium wishing all the world a very merry Christmas," says guest star Matt Lucas.

The Doctor Who Christmas Special will be the final episode for both Moffat and star Peter Capaldi. In an interview, ComicBook.com asked Moffat about the tradition of saying goodbye to Doctor Who stars at Christmastime.

"Oh god, is it? I guess," Moffat said. "I suppose Matt [Smith] left on Christmas Day, but Peter arrived on Christmas Day. David arrived on Christmas Day. So I mean, I don't know...I'm the first to leave on Christmas Day, I think.

"Oh, I don't know, I mean, truthfully, I think the audience is far more excited about welcoming in the new than sad about waving on the old. That's the truth of it is I think that's how I want them to feel, I want them to be excited about the future, not lingering on the past. We've had our day. And it was fantastic fun, but now it's time, more than anything, to want a new Doctor and a new showrunner and see a whole new, glittering future for the show, that's what I want to happen."

The Doctor Who Christmas Special airs tonight at 9 p.m. ET on BBC America.