Martin's grandson Vilhelm Beck is out on a routine mission with his supervisor when he finds a dead 17-year-old boy at the crime scene. It immediately becomes a case for Alex, Martin and the others in the Beck group.After a raucous youth party in a residential area outside Stockholm, one of the party-goers is found dead.

A man is found dead at a flea market in southern Stockholm. It looks like an ordinary robbery gone wrong, but the investigation takes an unexpected turn when the secret police (Säpo) take an interest in the case.

Josef is suspended, pending an internal investigation of his alleged assault of Säpo agent Klas Fredén, who has climbed to even higher heights within the police organization.