In a playground in the centre of the urban idyll, the police find a buried wooden box containing a famous and well-respected prosecutor. Martin Beck and his police team initially suspect a highly criminal MC-leader of the attack, but one pretty soon has to re-evaluate the case once the MC-leader is found murdered in a similar wooden box. Soon, more wooden boxes are found and the police realize that they are part of a cat and mouse game with a crazy serial killer. The investigation soon shows that there is a vague connection between the victims in the shape of a 9 year old event, but what Martin Beck does not suspect is that his own life too is at stake, as the murderer has chosen him as the next victim.

With the police closing in on his business Matt decides to get out before it is to late, however he is forced to deal with the unexpected.

JW now lives in exile and is more than ever determined to find out what happened to his missing sister Camilla. Every trace leads him to the world of organized crime in Stockholm. Jorge is about to do his last score – the largest robbery in Swedish history. But during the complicated preparations he meets a woman from his past – Nadja. Martin Hägerström is chosen to go undercover into the Serbian mafia, in order to get its notorious boss Radovan Krajnic behind bars. When an assassination attempt is made on Radovan, his daughter Natalie is pulled into the power struggle within the Serbian mafia.

Two missions taking place simultaneously in different decades where both C.I.S. Agents going under the alias Clank went up against the dangerous crime lord known as Goldscar.