A Batallion of the Spanish 'Blue Division' runs into a desolated landscape; a Cavalry Squadron frozen to death in a lake, their bodies still riding their horses. All but for one. His corpse lies on the ice; his throat slit. Engraved in blood on his shoulder reads 'Watch out, God is Watching You'. Soldier Arturo Andrade, a former police inspector, is assigned to the case. He proceeds methodically with the investigation with the aid of Sergeant Estrada. The clues lead them to conclusions of a perverse vengeance. Everyone is under suspicion, more than 18.000 people stuck in the cruel war. They are facing a serial killer who is a hunter in the snow.