Henry Dussard (Dean Jones), a young American, inherits a picturesque but badly neglected olive farm in southern France and is determined to make it operational again despite cautionary advice from the local priest (Maurice Chevalier) and a pretty villager (Yvette Mimieux). Desperate for laborers, the inventive Dussard turns to the zaniest crew of olive pickers ever recruited - four mischievous monkeys! As former members of an Air Force space team, these intelligent chimps quickly pick up on their new responsibilities - but prove to have a turbulent effect on the local townspeople.

Hank Dussard, a young American, arrives in France to claim the olive farm left him by his late uncle. He is welcomed by the local priest, Father Sylvain, who explains that olive farmers usually have large families since olives must be removed from the ground immediately after the seasonal wind blows them off the trees. Ignoring the hint that he take a wife, Hank imports four female chimpanzees, castoffs from past space flights, and trains them to be olive pickers. The news throws the village into an uproar, and the irate citizens stage anti-monkey demonstrations. Furthermore, Hank finds himself confronted by a phony cousin, Yolande, who claims half of his property. But Hank's pretty housekeeper, Maria, uses the chimps to frighten off the imposter and expose the fraud. Then, the mistral starts to blow, and crowds of curious townspeople gather to watch Hank's chimps harvest the olive crop. All is going well until Maria appears with a huge male chimp. And Hank is left alone as his female chimps pursue their new playmate through the olive grove. But Father Sylvain persuades the villagers to help Hank in his hour of need and all the local citizenry begin picking olives as Hank embraces the delighted Maria.