“Last Christmas” is the 2014 Christmas special for the new Doctor Who.
In the credits of “Death in Heaven”, the finale of the previous season, the Doctor suddenly sees Santa Claus (or Father Christmas if you prefer) in the TARDIS.
At the beginning of this episode Clara is woken up by noise outside the window on Christmas Eve. Investigating, she finds Santa Claus and two elves arguing as the sleigh has hit a chimney. Then the Doctor shows up (at this point he still thinks Danny Pink is alive; however he isn’t of course).
They next end up on a scientific base at the North Pole, where a team of scientists are doing something. Four of the team have been afflicted by a parasitic organism resembling the facehuggers from Alien – a fact that is mentioned and referenced.
The creatures are able to send people into a dream state. Which leads to the question – How do you know when you are dreaming? So for the entire episode you aren’t actually sure whether or not they are dreaming.
Michael Troughton guest stars – the son of Patrick Troughton, the Second Doctor.
The Doctor asks Clara that all important question – Do you believe in Santa Claus?