In Oslo on April 19th 1945, in the Third Reich's last days, a group of Nazis and sympathizers (a Wehrmacht general, an SS commander, his "assistant," an Italian industrialist and his wife who is also the general's lover, and a French collaborator) board a submarine that will take them to South America, where they hope to find refuge. While they sail in the Bay of Biscay, off the shores of the liberated French port of Royan, they manage to kidnap a French doctor to have him look after a wounded passenger. Dr. Gilbert will be forced to share the restricted space of the submarine with the fugitives. The atmosphere soon becomes unbreathable.