It's Christmas Eve in Naples. Little Rocco feels increasingly jealous due to the imminent birth of a baby brother. Three bungling devils sent by Satan promise him that if he'll stop Jesus from being born—entering the Nativity scene his father built by the magic word "opopomoz" and altering the past—his brother won't be born either.

The downfall of a powerful Mafia family by the hands of its young scion. Based on Aeschylus' tragedy, the Oresteia.