Bill Olsson is trying to gain a little extra income when he takes in a boarder, Karla, a woman with legal background who also has a side job as a part-time housekeeper for the Rytter family. The husband is a doctor and his wife is an invalid…when he doesn’t report for work one day, his absence is called in, and the police come to investigate….what they find is the beginning of a terrifying mystery that will monopolize the resources of their small community to a degree seldom encountered.