The body of a minor girl was discovered on the banks of the Main. An autopsy revealed that the victim spent many years in captivity, subjected to torture and sexual violence. The police do not have a single lead: they cannot even establish the identity of the murdered woman. But the investigation is helped by a chain of new crimes, seemingly unrelated. Someone is hastily covering their tracks, eliminating and intimidating witnesses in order to hide their shameful secret at any cost. Criminal police commissioners Pia Kirchhoff and Oliver von Bodenstein do not intend to stop until they bring her to light, even if the trail leads to the highest circles of society...