Actually, Bibi had imagined her school internship would be completely different. Because she missed the scheduled start date, she has to fill in as a museum attendant for two weeks instead. While her friend Marita is doing her internship with the police and Florian is working for the Neustädter Zeitung, it initially seems like Bibi is in for a rather boring time. That changes abruptly when an extremely valuable music box disappears from the museum...