In 1482 Paris, during the reign of Louis XI, 10 years before Christopher Columbus discovered America, sixteen-year-old Roma dancer Esmeralda is the romantic and sexual interest of many men, including Captain Phoebus de Chateaupers; poet Pierre Gringoire; the hunchbacked cathedral bell-ringer Quasimodo, and his guardian Archdeacon Claude Frollo. Frollo is torn between his obsessive lust for Esmeralda and the rules of Notre-Dame Cathedral. He orders Quasimodo to kidnap her, but Quasimodo is captured by Phoebus and his guards. After he saves her, Esmeralda becomes infatuated with Phoebus. Gringoire, who attempted to help Esmeralda but was knocked out by Quasimodo, unwittingly wanders into the "Court of Miracles", populated by the Roma and the truands. They are about to hang him for being an outsider, but Esmeralda saves him by agreeing to marry him. She only does it to save his life, however, and much to Gringoire's annoyance, refuses to allow him to touch her.
The following day, Quasimodo is sentenced to be flogged and turned on the pillory for two hours, followed by another hour's public exposure. He calls for water. Esmeralda, seeing his thirst, approaches the public stocks and offers him a drink of water. It saves him, and she captures his heart.
Frollo learns from Gringoire, with whom he has a passing acquaintance, that Esmeralda has taught her pet goat, Djali, who sometimes performs with her on stage, to spell "PHOEBUS" using movable letters, and that she often whispers the name Phoebus when she thinks she is alone. Frollo suspects Phoebus may be a name. As it happens, Phoebus is a drinking companion of Frollo's dissolute younger brother, Jehan. After seeing them set out for a local tavern, Frollo follows them. He learns that Phoebus has arranged an assignation with Esmeralda at a local boarding-house, and follows Phoebus there. He observes the meeting from an adjoining room. Esmeralda begs Phoebus to marry her, but Phoebus only wants to lie with her, and eventually seduces her. Inflamed with jealousy, Frollo stabs Phoebus, though not fatally. Esmeralda briefly faints, though not before she has caught a glimpse of Frollo. When she recovers, Frollo has fled, and she is found near Phoebus' body. Esmeralda is arrested and charged with the attempted murder of Phoebus and also with witchcraft, and is sentenced to death by hanging. The prison's torturer hurts her so badly that she falsely confesses to Phoebus' murder. While imprisoned, awaiting her execution, Esmeralda is visited by Frollo. The Archdeacon professes his love for her and promises to help her escape if she reciprocates. However, recognizing him as Phoebus' true attacker, she angrily rebuffs him. As Esmeralda is being led to the gallows, Quasimodo swings down from Notre-Dame and carries her off to the cathedral, temporarily protecting her – under the law of sanctuary – from arrest.
Frollo delves deeper into his obsession and gets frustrated with his plan failing. Upon seeing Esmeralda and Quasimodo when going to meet the latter, he grows jealous. That night he breaks into Esmeralda's cell with his master-key and attempts to rape her. Quasimodo intervenes and beats him, almost throwing him off the cathedral before the moonlight reveals his identity. Frollo kicks Quasimodo and declares to Esmeralda that if he can't have her, no one shall.
Frollo later informs Gringoire that the Court of Parlement has voted to remove Esmeralda's right to sanctuary so she can no longer seek shelter in the cathedral, and will be taken away to be executed. Clopin Trouillefou, the leader of the Roma, hears the news from Gringoire and rallies the Court of Miracles to charge Notre-Dame and rescue Esmeralda.
Quasimodo incorrectly assumes the approaching Roma intend to harm Esmeralda, and drives them off. As Quasimodo defends the cathedral against the invaders, the uproar reaches the king, who is incorrectly informed that those attacking the cathedral are eager for Esmeralda's hanging rather than trying to rescue her. The king orders the authorities to dispatch the invaders and calls for Esmeralda's immediate execution to settle the unrest. In the chaos, Esmeralda is taken from the cathedral by Frollo and Gringoire.
The king's men come to Notre Dame searching for Esmeralda. Quasimodo believes they intend to rescue her, and helps them, meaning that if she had still been there, he would have betrayed her.
Frollo once again attempts to win Esmeralda's love, but she asserts that she would rather die than be with him. Frollo goes to alert the authorities while trapping Esmeralda with Sister Gudule, a reclusive anchoress who bears an extreme hatred for the Roma as she believes they cannibalized her infant daughter. However, it is revealed that Gudule is really Esmeralda's birth mother and that Esmeralda is Gudule's long-lost daughter Agnes, abducted and raised by the Roma. The two women's joyous reunion is cut short when the king's men arrive to take Esmeralda to the gallows. A desperate Gudule clings to Esmeralda even as she is taken to the place of execution. The guards pull the old woman off her daughter, and she falls to the pavement and dies from the harsh impact.
From the tower of Notre-Dame, Frollo and Quasimodo witness as Esmeralda is hanged. Upon observing this, Quasimodo pushes the Archdeacon from the height of the cathedral to his death. With nothing left to live for, Quasimodo vanishes and is never seen again.
A deformed skeleton is found many years later embracing another in the charnel house, at of Montfaucon, implying that Quasimodo had sought Esmeralda among the decaying corpses and laid down to die while holding her. As the guards attempt to pull the skeletons apart, his skeleton crumbles to dust.
