Every Christmas we bring you a short story that involves the Doctor at Christmas, and this year we have a thrilling, three-part adventure called Behind You, written by Mark Williams.

The Doctor loathes panto but when the TARDIS brings him to the Palace Theatre at Christmas, 2014, he has more than bad puns and pantomime dames to worry about. Like the monstrous figures that stalk the backstage corridors, a mystery stretching back over a century and the possible destruction of the entire human race. The stage is set. Can the Doctor prevent tragedy on a terrifying scale or is it curtains for mankind?