In Normandy, the widower Auguste Maroilleur rules his family and his farm with an iron hand. Bien Phu, a disabled veteran of the war in Indochina, is a valued employee. Out shooting duck, Auguste and Bien Phu discover a huge cache of heroin. Auguste deduces that his grandson Henri, whose vacation job is on a ship, must be a courier. He destroys the drug, worth millions, and confines Henri to a cellar. When the gangsters cannot find their man or their merchandise, they try to destroy Auguste's livelihood and peace of mind. They burn a barn, brutally kill his cattle and rape his virgin granddaughter. He and Bien Phu fight back, eventually killing all five villains by shotgun and grenade. This private war does not go unnoticed and the police bring the whole family in for questioning. Following Auguste's orders, none of them give a thing away and all are released.

• Jean Gabin as Auguste Maroilleur, farm owner
• Marc Porel as Henri, Auguste's grandson
• Danièle Ajoret as Louise, younger daughter of Auguste
• Michel Barbey as Maurice, husband of Louise
• Christian Barbier as Léon, husband of Mathilde
• Pierre Dux as the investigating magistrate
• Armando Francioli as Francis Grutti, a gangster
• Julien Guiomar as the police inspector
• Eléonore Hirt as Mathilde, elder daughter of Auguste
• Reinhard Kolldehoff as Hans, a drug baron
• Astrid Frank as girlfriend of Hans
• Félix Marten as Marc, a gangster
• Orlane Paquin as Véronique, granddaughter of Auguste
• André Weber as Bien-Phu, farm worker
• Henri Attal as Louis, a gangster
• Dominique Zardi as Tony, a gangster
• Albert Delpy as A journalist

• "The Horse | Rotten Tomatoes". www.rottentomatoes.com. Retrieved 18 January 2024.

• Le Horse at IMDb