After being diagnosed with Dementia, an elderly war veteran is forced by his estranged family to hire a live-in nurse, only to find she harbors a sinister secret.

傳說中，聖誕白叟會獎勵乖小孩；聖誕魔鬼—坎卜斯（Krampus）則處罰壞小孩。當期盼已久的聖誕夜終於到來，來敲門的卻是聖誕魔鬼，想要避免成為坎卜斯的聖誕大餐，他們得聯手聖誕白叟一起抢救世界！