Impossible... Pas Francais on AllMovie

Two inept brothers, who cannot keep a job, call on their brother-in-law looking for work. He runs a detective agency, and they begin doing errands for him. They encounter a group of financiers who want a large shipment of a chemicals delivered from Portugal into France despite a transportation strike. The lads get hold of a boat and manage to evade the strikers, load the stuff on trucks, continue to evade the strikers, and make lots of money.