Cop Au Vin (1985)

When a small town of Normandy begins losing its citizenry in a series of strange deaths, out-of-town police inspector Jean Lavardin (Jean Poiret) is sent to investigate. Could the killers be a bullied son (Lucas Belvaux) and his possessive and manipulative mother (Stephane Audran) ? Or a pushy trio of local public figures and land developers wanna-be?