After the party for the winner of a violin competition, music professor Karin Landauer embarks on an erotic adventure with his brother. When she returns from the bathroom to the bedroom, she finds the young man murdered. Now the infidelity cannot be kept secret from her husband, an internationally renowned violin virtuoso. But the fact that the 300- year-old Stradivarius, "The Sleeping Beauty", which belongs to his wife, has disappeared from the apartment hits him far harder than the adultery. Inspector Moritz Eisner does not really believe in robbery and murder and begins to examine the private and professional situation of the artist couple. He soon finds out that their marriage hasn't been as happy as it seems on the outside for a long time.