Librarian Mathias Geyer was stabbed at the city library. He last worked on the inheritance of a noble family from Rosenheim. Did he find something that turned out to be his deadly curse? He had sent scans to Professor Corinna Sander. During a conversation with her the cops notice that she is hiding something. They also wonder whether an argument between Geyer and the archivist Hoppe got out of hand when the case takes a surprising turn.