Cop au Vin (1985) on Netflix

Plot summary

Louis delivers the mail in a small French town and shares a big, crumbling house with his mother, who is disabled and eccentric and whose demands fill his evenings. The post office clerk, Henriette, makes advances he does not return. The rest of his time goes to watching the three men he calls his enemies: Lavoisier the lawyer, Morasseau the doctor and Filiol the butcher, leading citizens who have banded together to buy his house and redevelop it. Louis and his mother turn down every offer, and the three reply with constant harassment. When Filiol is especially obnoxious, Louis slips sugar into the fuel tank of his car overnight, and the crash that follows kills Filiol and brings the inspector Jean Lavardin to town.