1945年,刚被同盟国释放的法国医生Guilbert在Royan被纳粹逮捕。他们把他带到一艘意图前往南美洲的潜水艇上。船上有一个盖世太保的头目,一位德国将军,一个意大利商人和他妻子,几个逃亡者,其中一位亲德的法国记者(Couturier饰)。于是多方利益交织冲突就在这艘逃亡的潜艇上发生了。Oslo, April 19th 1945, as the Third Reich is living its last days, a group of Nazis and sympathizers (a Wehrmacht general; an SS commander and his "assistant"; an Italian industrialist and his wife who is also the general's lover; 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...