He gets home at dawn, when she's putting out the trash. She vacuums when he's trying to get to sleep. He starts playing the piano right when she's putting her kids to bed. They live in neighboring apartments, but they're a world apart. She's Dorine, the building super who struggles with her uncaring husband, her four and one half children and the afternoon TV soaps. He is Louis Le Bison, a slightly gruff 30-year-old, a fast liver who has seen it all.
When her husband leaves with his lover, both their lives are turned upside down. At first reticent about a family which is so foreign to him, Le Bison comes to their rescue in spite of himself. He, the hedonistic dilletant, is drawn into an infernal machine, winds up involved in Dorine's life, taking her place, taking out the garbage and delivering the mail.
Thanks to the incredibly adult, calm and confident children, Louis Le Bison finally gets a taste of the pleasure of being alive, the pleasure that comes with action.