A missing child. A desperate father. A terrible secret. 

Guido T has already confessed to two horrific child murders and led Berlin police to the bodies. The police are sure he is also the kidnapper and murderer of six-year-old Max, who disappeared without trace a year ago. But now the killer is staying silent. The investigators have no reliable evidence, so Max's parents have no certainty and are unable to say goodbye to their son.

Everything changes when one investigator makes an unbelievable offer: he can have Max s father placed in the psychiatric prison hospital where Guido T is imprisoned as a fake patient. Max s father agrees. He plans to force the child killer into a confession. Because nothing is worse than uncertainty. Or so he thinks. Until he, as an inmate, learns the gruesome truth...