Just how did the happiest day of the year slip into a welter of blood, innards and shambling, ravenous undead on the snowy streets of old London town? Will the ghosts of Christmas Past, Present and Future be able to stop the world from drowning under a top-hatted and crinolined zombie horde? Was Tiny Tim's illness something infinitely more sinister than mere rickets and consumption? Can Scrooge be persuaded to go back to his evil ways, travel back to Christmas past and destroy the brain stem of the tiny, irritatingly cheery Patient Zero? It's the Dickensian Zombie Apocalypse ....