Below is a PDF on real world points of view on the special ranging from Facts, Cast lists including producers and myths about the episodes.
The Christmas Invasion was the first episode of Doctor Who to be broadcast on Christmas since "The Feast of Steven", the seventh part of the 1966 serial The Daleks' Master Plan.
However, unlike that serial, The Christmas Invasion was specially commissioned by BBC One to be transmitted outside of the programme's normal broadcasting season. It was thus the first in the modern tradition of the "Christmas Special", and
its sixty-minute runtime made it then the longest episode yet produced by BBC Wales.
Narratively, it was important for continuing the story of Harriet Jones, starting the Torchwood story arc, and involving UNIT in its first "major" appearance in the new series.
However, it was far more significant for being 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, because its setting was both the first and last place on Earth the Tenth Doctor saw.
S Y N O P S I S
It's Christmas Eve and high above London, the alien Sycorax are holding the Earth to ransom. The Doctor must recover from his regeneration in time to save the human race from slavery.
P L O T
It is Christmas Eve on Earth. As Jackie prepares presents and Mickey works in the garage, both of them hear the distinctive sound of the TARDIS' engines. Rushing out into the street of the Powell Estate, they see the TARDIS blink into existence above them, ricochet off a few buildings and a post van, then come to a crashing halt. A strange man stumbles out of the police box doors, greets them by name and wishes them
a merry Christmas before collapsing. Rose follows and, in response to Jackie and Mickey's questions, identifies the stranger as the Tenth Doctor.
They bring the Doctor to Jackie's flat and dress him in pyjamas belonging to Howard, Jackie's current beau, who has the habit of keeping pieces of fruit in his pocket for snacks. While Rose discusses the Doctor's change of appearance and the fact he has two hearts with Jackie, they do not see a wisp of vortex energy emerging from the Doctor's mouth, which then floats into space. On television, Prime Minister Harriet Jones and project director Daniel Llewellyn give a press conference about the Guinevere One space probe, which is about to land on Mars. In space, however, the probe is swallowed up by an island-like spaceship.
That evening, Rose and Mickey go Christmas shopping, but are attacked by a group of masked Santa's armed with lethal
musical instruments…………