SPOILER WARNING: The following article contains spoilers for the Doctor Who Series 10 finale.
It looks like fans are going to get a double helping of the titular Time Lord in this years' Doctor Who Christmas special, as Peter Capaldi's Twelfth Doctor is set to team up with his own original incarnation -- the First Doctor -- as played by Game of Thrones star David Bradley.
Bradley, who can be seen as the First Doctor in the closing seconds of the show's recent series 10 finale, is no stranger to the show, and has previously featured as the villain Solomon in the 2012 episode "Dinosaurs on a Spaceship." He also played the original First Doctor actor William Hartnell in the 2013 Docudrama An Adventure in Space and Time, which dramatised the circumstances around the genesis of the long-running sci-fi series.
This time around Bradley will be playing the Time Lord himself and, if the ending of the show's season 10 finale is any guide, the Christmas episode will be set in the snowy wastes of Antarctica on the brink of the First Doctor's regeneration at the end of the 1966 story "The Tenth Planet."
The Christmas episode will also be Steven Moffat's last as its showrunner before the arrival of his replacement Chris Chibnell, who has written a number of the show's past episodes, including the aforementioned "Dinosaurs on a Spaceship."
The as-yet untitled 2017 Doctor Who Christmas special does not have a firm set broadcast date, but in the past few years such episodes have usually been broadcast on Christmas Day on both BBC One and BBC America.