It is Austria, Krampusnacht, December 1977. Julian Devonshire, his pregnant wife Kathy, their son Toby and mother in law Celia arrive at the alpine chalet for a family holiday. They are shown around by Klaus who tells the family about the local legend of The Devil of Christmas. All the good children are given gifts by St. Nicholas, and all the bad ones are punished by the demonic Krampus. But who has been good, and who has been bad?