Imbued with the spirit of the left-wing political movement, the Popular Front (France), which would have a major political victory that year, the film chronicles the story of M. Lange (René Lefèvre (actor)), a mild-mannered writer at a publishing company who writes Western stories for it. Batala (Jules Berry), the salacious owner of the company, flees his creditors; when the train he is on crashes, he takes the opportunity to fake his own death. The abandoned workers, with the help of an ecentric creditor, decide to form a cooperative. They have great success with Lange's stories about the cowboy, Arizona Jim, whose stories parallel the real-life experiences of the cooperative. At the same time, Lange and his neighbor, Valentine (Florelle), an old flame of Batala, fall in love.