The annual one-day fair comes to the small town of Sainte-Severe-sur-Indre, where the postman François is ridiculed for his outdated methods. Despite the importance of his job, François remains skeptical, and in the evening, he's tricked into watching a stunt show disguised as a US postal delivery demonstration. Sobering up the next day, François reorganizes his delivery methods using only his bicycle, making humorous progress.