A woman is found murdered in a closed amusement park. A young couple who happen to be there at the same time become, without their knowledge, suspects for the murder. They are chased by a large number of police but only Martin Beck believes them to be innocent.

Frank, Sara and their two children have recently moved into the house of their dreams on the countryside. Frank is disturbed by mysterious sounds and somebody tears down the wallpaper from the walls. He contacts a ghost-hunter, Allan, to find out the truth.