Set on Discworld, Terry Pratchett's Hogfather novel is brought to life. Deranged Assassin Mr Teatime (with a bunch of thieves and a failed apprentice wizard) wants to "inhumme" the Hogfather (discworld's equivalent of Santa Claus) by destroying children's belief in him. By kidnapping and holding hostage the tooth fairy in order to use children's teeth to control their belief. The only being that can take his place? Death, a depressant Anthopomorphic personification, too caught up with humanity for his own good. Assisted by his foul servant Albert and his half-human (beacause some talents, like walking through walls or freezing time, are inherited "in the bone" rather than genetically), adoptive granddaughter Susan this is fantastic mash up of magic, monsters and fantasy.
