Donissan (Gérard Depardieu) is a very zealous rural priest of the Catholic Church in 1920s Pas-de-Calais. The Dean (Christianity) Menou-Segrais (Maurice Pialat) tries to keep him reasonable. But Donissan will be tempted by Satan, then will try to save the soul of Mouchette (Sandrine Bonnaire), a young girl who killed one of her lovers.