Auteuil's Antoine is the seasoned headwaiter at an elegant Paris restaurant. Not only is he an invaluable employee, but he's also a good-hearted man quick to solve other people's problems. His dedication has already made him late for a dinner date with his live-in lover, Christine (Marilyne Canto), when, while taking a short cut through a park, he witnesses a young man, Louis (Garcia), attempting to hang himself. The instant Antoine saves Louis' life he immediately starts carrying the creed of being "my brother's keeper" to hilarious extremes.

Louis is a big, solidly built teddy bear of a man with a boyish face and dark moist eyes — and the very embodiment of emotional immaturity. His girlfriend, Blanche (Kiberlain), has left him, and his self-pity is so complete that only Antoine could have a prayer of pulling him out of his misery — and not surprisingly at often comic but also real cost to Antoine's own happiness and security.

Gradually, Antoine comes to believe that only his tracking down Blanche and effecting a reconciliation between the two will truly restore Louis. But when Antoine finally succeeds in locating Blanche, who is running a flower shop not far from the restaurant, he is not prepared to find himself attracted to this exquisite young woman….