On the banks of the River Isar, Jakob Arndt and Ben Ritter, both aged 12, have built a small campfire. It’s a remote, secret place where the two of them meet after school, only being forced to go home when darkness falls. But home doesn’t really draw Jakob. His mother, Carmen, and her husband, Urs Wolfram, Jakob's stepfather, grow concerned but don’t alarm the police about Jakob’s disappearance until late in the night. Too late as it turns out, for the next morning the boy’s body is discovered among the scrap vehicles at a remote junkyard.
The detectives from the Munich Criminal Investigation Department immediately start their questioning, but ca'’t find any plausible motive for the crime among those who knew the murdered boy. They don’t even have any hard and fast evidence against the main suspect, Heiner Wittmann, the owner of a flea market. Then Leo Kress and his colleagues are called out to a new crime scene. Barbara Rehling, an attractive and wealthy woman, has been found by her nephew bludgeoned to death in her home. More or less by chance it turns out that the woman's house is on murdered Jakob's route to school. Ben confirms that he and his friend had often peered through the windows. Are the two cases in some way connected? Is Jakob's murderer also to be sought among the suspects in the rich woman’s murder case? An apparently insignificant find in the basement of the woman’s house at last provides the investigators with the vital clue...
