Inspector Rolf Spiekermann is committed and successful, but has many enemies in Hamburg's underworld and little time for his family. That's why his wife Elke and the children are looking forward to vacationing together in Amrum. Arriving on the idyllic island, Rolf falls victim to a treacherous attack. With the help of the young hitchhiker Olaf, he gets off lightly. Rolf feels at the mercy of an invisible opponent. Because the local police only investigates half-heartedly, he tries to find the perpetrators himself. But inspector Spiekermann has found that all his professional skills cannot help him.