The Christmas Invasion

During the classic run of Doctor Who there was really only one instance of the show acknowledging Christmas, and the canonical status of that episode has been heatedly debated ever since. In the middle of the now mostly lost serial The Daleks' Master Plan was an episode called "The Feast of Steven." That particular episode was a complete diversion from the main story, to the point where it wasn't even sold to foreign distributors along with the rest of the serial and thus will likely never be recovered. It aired on Christmas Day in 1965 and at the end of the episode William Hartnell, the First Doctor, turned to the camera and wished everyone at home a Merry Christmas. No one knows for sure if this was part of the script or if Hartnell was merely ad libbing, as it was apparently common practice for BBC shows airing on Christmas Day to directly address the audience. This breaking of the fourth wall has been a thorn in the side of fans who feel the need to understand and justify the show's various disruptions in continuity.

All of this is just a long winded way of saying that when the show was revived in 2005, the idea of a special Christmas episode probably wasn't something anyone was expecting. The revived show initially starred Christoper Eccleston as the Ninth Doctor, though it wasn't very long into his run when it was announced that David Tennant would be taking over the role. The Christmas Invasion was Tennant's first adventure as the Doctor, even though (much like Jon Pertwee) he spent most of that first adventure in bed. The Tenth Doctor, who would go on to become probably the most popular Doctor of the revival series, got a great introduction in this special. He comes off as a real goofball with a deadly serious side. In the end, he chooses to spend Christmas Day with Rose and her family but only after he defeats the leader of an alien invasion in a sword fight and then topples the British government. 

Rating: Not bad for a man in his jim jams%

(Image from Youtube)