Bloody nightmare in a camp outside the city. Can Joona Linna solve the case with the help of a hypnotist?

In the middle of the night, someone calls 911 that a burglary is in progress at a closed campsite outside Stockholm. The nearest police car responds to the call, and when the patrol arrives at the scene, they are met with a terrifying sight in one of the caravans. The floors, walls and furniture are completely covered in blood. Someone was killed there with an ax and brutally dismembered.

Not far from the crime scene, a young man sleeps on the floor with a severed arm that serves as a pillow. The young man is immediately arrested and taken into custody. This is the barely seventeen-year-old son of a famous writer. It soon turns out that he suffers from a rare kind of sleepwalking. The young man may be the perpetrator or a witness to the entire massacre, but he does not remember anything.

Joona Linn, who takes on the case, asks his old friend Erik Maria Bark to use hypnosis to find out what happened in the caravan.