Two years earlier, just before the defeat of France by the Germans, five convicts who escaped from Devil's Island are found adrift in a small canoe in the Caribbean Sea by the tramp steamer "Ville de Nancy". These five men, Marius (Peter Lorre), Garou (Helmut Dantine), Petit (George Tobias), Renault (Philip Dorn), and their leader, Matrac, are rescued and taken aboard the French freighter commanded by Captain Malo (Victor Francen). Later, when confronted by Captain Freycinet, the five confess to being escaped convicts from the French prison colony at Cayenne in French Guiana. They had been recruited by Grandpère (Vladimir Sokoloff), a fervently patriotic ex-convict, to fight for France in her hour of need. To Grandpére, the inmates had recounted Matrac's troubles in pre-war France to convince the old man to choose Matrac to lead the escape. A crusading newspaper publisher, Matrac, being opposed to the Munich Pact, had been framed for murder to shut him up.