Walter König (Schnitzer), the owner of an Italian restaurant, receives demands for protection money, but refuses to pay. Mafia thug Johannes Dohna (Kohlund) is sent to give König a final warning, but in an altercation ends up killing him. He flees, and leaves his daughter Vera (Scholze) behind. When Derrick arrives at the suspect's apartment, he finds Vera there, and realizes she is the key to catching the murderer.