In a dilapidated apartment building in a post-apocalyptic France, food is in short supply and grain is used as currency. On the ground floor is a butcher’s shop, run by the landlord, Clapet, who posts job opportunities in the Hard Times paper as means to lure victims to the building, whom he murders and butchers as a cheap source of meat to sell to his tenants.
Following the murder of the last worker, unemployed circus clown Louison applies for the vacant position. During his routine maintenance, he befriends Clapet’s daughter, Julie, a relationship which slowly blossoms into romance. Louison proves to be a superb worker with a spectacular trick knife and the butcher is reluctant to kill him too quickly. During this time several of the tenants fall under Louison’s boyish charms, worrying others who are more anxious for their own safety should they require meat. Aware of her father’s motives, Julie descends into the sewers to make contact with the feared Troglodistes, a group of vegetarian rebels, whom she persuades to help rescue Louison.
During the apparent butchering of an old woman, the Troglodistes attack but are repelled, and Clapet, with the unsympathetic tenants, storms Louison’s room in an attempt to murder him. Louison and Julie resist by flooding themselves, floor to ceiling, in an upper floor bathroom until Clapet opens the door releasing the flood and washing the attackers away. Clapet returns with Louison’s knife and inadvertently kills himself. Louison and Julie play music together on the roof of the now peaceful apartment building.