August 1945. In a remote mill in American-occupied Württemberg, a quintuple murder takes place. The miller and his wife, their two sons, and their daughter Irma were executed, and the daughter was then hanged and smeared with SS runes. However, a young refugee woman named Karin Katte, whose origins and history are unknown to anyone in the village, survived the massacre by chance. The investigation is led by Dave Gladbaker, a Jewish employee of the American secret service whose parents were murdered in a concentration camp. His investigations soon focus on Karin Katte, who Gladbaker suspects must have been the real target of the attack. Katte is suspected of being a former concentration camp guard.