Another dead body in the Lichtenstein cave! But this one is not from prehistoric times; it belongs to the present. And he was not among the few living descendants of the Bronze Age people from Lichtenstein. This was revealed by the spectacular DNA comparisons. But why did Franz Krüger have to die in his cave, of which he considered himself the discoverer? And then another murder occurs, this time right in Osterode. Chief Inspector Behrens and his team are on the hunt for a mysterious black monk who keeps appearing at the crime scenes.