In Nazi-occupied France, the German command attempts to establish cooperation with the local authorities. The compliant citizens are being recruited into the Third Reich, but within the ranks, there is distrust towards representatives of the "inferior" races. Simona Strasser, a German woman who has lived her whole life in France, joins the Gestapo. Her brother, Frank, a submarine officer, asks her to deliver something to an acquaintance before his departure for training. Their meeting is disrupted by a raid, and later Simona learns that Frank has been involved with the underground resistance all along.