A writer about today's youth gets a chance to give a roof to two young hippie girls in a stormy night. They were travelling alone when they had a car accident, so they prepare for a bath and sleep, but decide to seduce their host.
Come morning and he asks them to leave as he is afraid his wife and children are about to return. But the two nice young girls reveal they true nature, scorning at him.
He leaves for a conference believing he manage to get rid of the pair, but returns to find they have invaded the house once again. They take over him, keep him hostage while they feed themselves on drugs, sex and violence. And finally, on murder!