The Christmas Invasion was the 2005 Christmas Special of Doctor Who.
It was the show’s first Christmas special since its revival and the first Christmas special starring David Tennant as the Doctor.
It was the first episode of Doctor Who to premiere on Christmas Day since “The Feast of Steven”, the seventh part of 1966 twelve-part serial The Daleks’ Master Plan. However, unlike that episode, The Christmas Invasion was specially commissioned by BBC One to be transmitted outside the programme’s normal broadcasting season. It was thus the first in the modern tradition of the “Christmas special”, and its sixty-minute running time made it then the longest episode yet produced by BBC Wales.
Narratively, it continued the story of Harriet Jones, started the Torchwood story arc and involved UNIT in its first major appearance in the new series.
More importantly, it was the first full story to feature the Tenth Doctor, played by David Tennant. Its initial pre-titles sequence on the Powell Estate was later used to “bookend” the closing scenes of The End of Time. Its setting was the first and last place on Earth the Tenth Doctor saw.
To coincide with this release, three short stories were released on the U.N.I.T. website. The first was Alien Life, part of the UNIT Press Briefings mini-series, which was set directly in the aftermath of the Sycorax invasion, where UNIT confirms that aliens exist, and the second and third, Guinevere One and Project Rooftop, part of the Operations Board mini-series, was set during and after The Christmas Invasion, respectively, depicting events of the television story from UNIT’s perspective.
