An ex-convict, troubled by dreams that he strangles women, is hired as the caretaker on an estate owned by three very strange sisters. Soon after his arrival, a serial killer begins slaughtering blonde, blue-eyed women - and leaving their eyeballs in a bowl of water.
The legendary Loreley has been living for centuries in a grotto beneath the river Rhein in Germany. Every night when the moon is full, she turns into a reptile-like creature craving for human blood. When one girl after another of a nearby boarding school is killed by her, a hunter named Sigurd is engaged to kill the monster.
