Elisabeth and Gudrun are two Swedish divorcées, both over 40, who meet when Elisabeth parks her car on a loading zone and is ticketed by Gudrun. Despite this shaky start, a friendship grows between the two. Elizabeth, a gynecologist, is sexy and confident. She leads the shy Gudrun through the dangerous waters of single life. But as they cavort through the dance floors and bars of Stockholm's nightlife they are led to a deeper examination of the relationships with men.

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.