Far away from their native France, two men are in trouble in a Mexican town. One is gentle missionary monk Brother Benoît; the other is tough, stubborn boxer Antoine Capella. Brother Benoît has saved a chimp he calls Mookie and made his pet, but it's a talking monkey, which is why a group of scientists want to take it away from him. As for Capella, he has refused to lose a rigged fight and now a gang of badmen are after him to punish him. When the two men are forced to leave the town, they decide to travel together to Mexico. The road will be long and eventful.