Garbed in his red suit, Harry, a toy factory worker, decides that the only thing he can do to save the spirit of Christmas is to become Santa Claus himself and make all of the naughty townspeople pay... in blood!

The story revolves around a Basque Roman Catholic priest dedicated to committing as many sins as possible, a death metal salesman from Carabanchel, and the Italian host of a TV show on the occult. These go on a literal "trip" through Christmas-time Madrid to hunt for and prevent the reincarnation of the Antichrist.