The people of North Frisia live in fear and terror. An arsonist is on the loose. He has already set 14 fires - five of them alone in Risum-Lindholm. The police have no leads. Then the primary school in the village falls victim to the arsonist, and in the teachers' room of the burned-down building, the fire department discovers a charred female corpse. The criminal police assume it was an accident, but Commissioner Dirk Thamsen and his friends Haie, Tom, and Marlene suspect that a copycat is behind it, trying to cover up a murder.