While performing at the Topsy Turvy Club, Esmeralda meets Quasimodo Bell, a shy young worker from a local circus. Quasi spends most of his days backstage as a strongman, but occasionally endures taunting in the sideshow, where he's billed as "the Hunchback." Before meeting Esmeralda, Quasi's only friends were Vic, Hugh, and Laverne, three disfigured dwarfs who also perform in his troupe. Sneaking into this speakeasy is his first time breaking the law.

Esmeralda is shocked to learn that Quasi’s foster-father is none other than Claude Frollo. Frollo is a judge considered racist even for his time, venomously obsessed with enforcing Prohibition, and using it to harass minorities at any opportunity. Frollo pushed Quasi into the circus career, convincing him that it was all he'd ever be good for, in spite of Quasi's artistic talents. Esmeralda can't believe someone as cruel and bigoted as Frollo could have raised someone as kind as Quasimodo. The surprises continue when Chief of Police Phoebus Gold turns out to also be incredibly progressive and noble, and a romance begins.

Judge Frollo develops a twisted fixation on Esmeralda, after witnessing her “sinful” performances around town, and being publicly challenged by her when he refuses to stop a mob from harassing Quasi at the sideshow. Quasi and the Chief track Esmeralda to an underground speakeasy called the Court of Miracles, to warn her that Frollo is planning a raid. Unfortunately, Frollo used Quasimodo and Phoebus to lead them right to the hideout.

Now completely unhinged, Frollo cuffs Esmeralda to the bars of her prison cell and douses her in alcohol, planning to “burn the witch in her own sin.” But just before the deranged judge can drop the match onto her, Quasi breaks through the bars of his cell, and sends Frollo across the jailhouse in a swipe of his arm. A mass jailbreak ensues, followed by an epic brawl, with some cops like Phoebus joining the wrongfully imprisoned citizens against Frollo’s corruption. Frollo ends up falling off the highest part of the Grace Memorial Bridge, to his long-overdue demise. Quasimodo is hailed as a national hero, and the city celebrates. Quasi eventually finally finds love with a gun moll named Maddy, who betrays her scam-artist boyfriend Sarouch and turns a new leaf.