The novel is set in France.
In Rheims, Paquette de Chantefleurie gives birth to a pretty baby girl. Then some Gypsies steal her baby and replace it with an ugly baby boy who is a hunchback. They take away the shoe of one leg of the baby and leave the other behind. Paquette goes to Notre-Dame and becomes a recluse known as "Sister Gudule". She curses every Gipsy she sees from the window of her room. She keeps the shoe left behind by the Gypsies.
The Gypsies rear Paquette's daughter and she becomes the beautiful La Esmeralda. She dresses like a Gipsy, sings and dances beautifully and takes a goat around with her. She also carries her second shoe (taken by the Gypsies when they stole her) around. Meanwhile, the hunchback baby boy is adopted by the archdeacon of Notre-Dame , Claude Frollo, an orphan who has reared up his younger brother, Jehan. The hunchback is named Quasimodo and becomes
the ringer of church bells in Notre-Dame. The noise of the bells make him deaf with time.
Sister Gudule keeps looking for her daughter and La Esmeralda for her mother. Sister Gudule curses La Esmeralda whenever she sees her, seeing her as a Gipsy.
La Esmeralda has once saved Pierre Gringoire from the gallows by marrying him but wards off his amorous advances with a dagger she always carries ground. She also gives Quasimodo some water to drink when he is pilloried and nobody else is willing to give him water. Quasimodo is eternally grateful to her for this. Her undoing is falling in love with one Captain Phoebus de Châteaupers ,the lover of rich Fleur-de-lys de Gondelaurier.
While Fleur-de-Lys hates her because of Phoebus, the archdeacon wants her for himself. One day, Phoebus and Esmeralda enter a hotel room but the archdeacon stabs him from behind and everyone thinks she did it . She is sentenced to death by hanging, though Phoebus is not really dead. Quasimodo carries her to a sanctuary, from where the archdeacon and Pierre take her away in a boat. While Pierre is busy with the goat, the archdeacon asks her to choose between accepting his love advances and death by hanging. She defiantly chooses the latter so he takes her to Sister Gudule's cell and goes to call the soldiers. However, Sister Gudule and La Esmeralda get talking and discover they are mother and daughter when the shoes in their hands matched. Sister Gudule quickly changes from her enemy to her protector.
Sister Gudule will have succeeded in hiding her from the soldiers, if she has not heard Phoebus' voice and shouted his name. Sister Gudule bites the hangman but pays for this with her life. The archdeacon watches Esmeralda's hanging with great pleasure from the top of the church tower. Quasimodo pushes him down from behind and he dies. Quasimodo flees Notre-Dame but his skeleton is found entwined with Esmeralda's 2 years later. Pierre Gringoire saves the goat and Phoebus marries his Fleur-de-lys.
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* "Gipsies" = "Gypsies". Both spellings are correct.