A corpse is found in the Bay of Wilhelmshaven. It soon becomes clear that the dead man was an officer in the Dutch KFOR troops in Kosovo. During his investigation, Chief Inspector Holzer meets sailing instructor Michael Kühnert and his deaf wife Elena. Their way of communicating with each other and their daughter Sabin in sign language arouses his interest. Although Kühnert admits that he used to be a KSK soldier in Kosovo and met Elena there, neither of them claim to know the deceased. Holzer is certain that they are hiding something from him.
