The story is set in Paris in 1482. Quasimodo is a deaf, half-blind, hunchbacked bell-ringer of the famous Cathedral of Notre Dame in Paris. His master Jehan, the evil brother of Notre Dame's saintly archdeacon Don Claudio, prevails upon the hunchback to kidnap the fair Esmeralda, a dancing gypsy girl (and the adopted daughter of Clopin, the king of the oppressed beggars of Paris' underworld). The dashing Captain Phoebus rescues Esmeralda from Quasimodo, while Jehan abandons him and flees. At first seeking a casual romance, Phoebus becomes entranced by Esmeralda, and takes her under his wing. Quasimodo is sentenced to be lashed in the public square. After being whipped, he begs for water. Esmeralda pities him, and brings him some.

To their dismay, Jehan and Clopin both learn that Phoebus hopes to marry Esmeralda, despite being engaged to Fleur de Lys. Phoebus persuades Esmeralda to accompany him to a ball celebrating his appointment as Captain of the Guard by King Louis XI. He provides her with rich garments and introduces her to their hostess, Madame de Gondelaurier, as a Princess of Egypt. Clopin, accompanied by his beggars, crashes the festivities and demands Esmeralda be returned. To avoid bloodshed, Esmeralda says that she does not belong with the aristocracy. Later, however, Esmeralda sends the street poet Pierre Gringoire to give Phoebus a note, arranging a rendezvous at Notre Dame to say goodbye to him. Before Phoebus arrives, he is stabbed in the back by Jehan. After Esmeralda is falsely sentenced to death for the crime, she is rescued from the gallows by Quasimodo and carried inside the cathedral, where he and Don Claudio grants her sanctuary.

Don Claudio restrains Quasimodo from violence.
Later that night, Clopin leads the whole of the underworld to storm the cathedral, and Jehan attempts to take Esmeralda, first by guile (telling her that Phoebus's dying wish was for him to take care of her), then by force. Quasimodo holds off the invaders with rocks and torrents of molten lead. Meanwhile, the healed Phoebus is alerted by Gringoire and leads his men against the rabble. When Quasimodo finds Jehan attacking Esmeralda, he throws his master off the ramparts of Notre Dame, but not before being fatally stabbed in the back. Phoebus finds and embraces Esmeralda. Witnessing this, Quasimodo rings his own death toll, and Gringoire and Don Claudio enter the bell tower just in time to see him die. The last image is of the great bell swinging silently above the hunchback's corpse.