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.

Quasimodo is still a baby when is taken in by Archdeacon Frollo and is turned into the bell-ringer.