Cyprien and his friends Hector Colomb and Annette are penniless and desperate. They need someone to take an interest in them. One day, they decide to become volunteer castaways. To build their raft, they sawed down trees in the Bois de Boulogne. With the support of Caroline Grossac and her mother, they were backed by M. Grossac, a comfortable businessman with a keen sense of publicity. Launched in Saint-Tropez, the raft made only a short crossing. Nevertheless, the new privateers are acclaimed, and the wilful shipwreck business is so successful that it makes Hector and Annette rich, while Cyprien marries Mlle Grossac.