After losing his faith in Christmas and tearing apart his letter to Santa, a young boy (Emjay Anthony) accidentally summons the malevolent holiday demon Krampus. The following day, his family awaken to find that a massive blizzard has knocked out the power in their house, and they are soon forced to fight for survival as the fearsome folklore creature and his minions proceed to wreak havoc on the dysfunctional clan. Adam Scott, Toni Collette, and David Koechner co-star in this hybrid of black comedy and horror from director Michael Dougherty (Trick 'r Treat).