In a French port city, a handsome and enigmatic sailor named Querelle arrives on a naval ship. Unbeknownst to his shipmates, Querelle is involved in drug smuggling and harbors dark desires. He ventures into a seedy world where violence and sexual intensity are intertwined, finding himself at La Feria, a brothel and opium den run by Lysiane. Engaging in a peculiar relationship with her lover, Nono, the brothel's owner, Querelle begins to explore his latent homosexual tendencies amidst the sin and shadows of the city. His journey through La Feria becomes a labyrinthine descent into his own psyche, testing boundaries of loyalty, betrayal, and self-discovery.

Querelle's interactions with others expose the deep layers of his character as passion and brutality intermingle. His brother Robert, unaware of Querelle's secret life, becomes an involuntary participant in the unfolding drama. Meanwhile, Lieutenant Seblon, who harbors unspoken feelings for Querelle, wrestles with his own inner turmoil. Amidst theft, murder, and lust, Querelle's turbulent voyage pushes him to confront the monstrous and seductive aspects of human nature that lurk within. The narrative delves into complex themes of power and identity but leaves many of Querelle's ultimate fates ambiguous, creating an air of lingering tension and unresolved conflict.