The title of this French "reality" drama, which translates to Before the Deluge, is a play on Louis XVI's famous prognostication, "Apres moi, le deluge." Set in 1950, the film concentrates on five Parisian adolescents. Certain that the next war will herald the apocalypse, the youngster make plans to run off to a desert island and set up a new society. This, however, will require money, which is why the boys decide to pull off a "necessary" robbery. Idealism collapses in the face of cold reality, as the five youths suffer from the consequences of their actions. Avant le Deluge was one of a group of films cowritten by director Andre Cayatte and Charles Spaak which endeavored to explore the touchy social issues of the day: others in the Cayatte-Spaak canon include the euthanasia-themed Justice est Faite and the capital-punishment tract Nous sommes tous des assassins.

Stefan Borba was a member of a spy ring during the war but after the end of the conflict he opted out. Now he is a miner in Belgium and lives happily there with his wife Denise. Unfortunately for him, his past catches up with him. One day indeed, Milan, a secret agent with whom he used to work, resurfaces and forces him back into action...