A westbound ship bound for Apia, Samoa, is temporarily stranded at Pago Pago due to concerns about a possible cholera outbreak on board. Among the passengers are Alfred Davidson, a self-righteous missionary, Mrs. Davidson, and Sadie Thompson, a woman whom Davidson condemns as immoral. Thompson spends her time aboard the ship partying and drinking with the American Marines stationed on the island. Sergeant Tim O’Hara, known to Sadie as "Handsome," quickly becomes smitten and pursues her with a quiet persistence. The dynamic on board sets the stage for a clash between judgment and desire, under the constant hum of the tropical environment.
Thompson's carefree behavior provokes tension with the Davidsons, and Alfred Davidson confronts her with the aim to "save her soul." When she dismisses his offer, he uses his authority to have the Governor order her deported to San Francisco, where she is said to be wanted for an unspecified crime (which she insists she was framed for). She pleads to remain on the island for a few more days, hoping to slip away to Sydney, Australia, planning a chance to start anew. The island’s authorities and the governor’s decree underscore the clash between morality as Davidsons’ creed defines it and Thompson's lived reality.
During a heated argument, she experiences a religious conversion and agrees to return to San Francisco to face the jail sentence awaiting her there, a moment that shifts the tone of the tale from condemnation to ambiguous opportunity. The evening before departure, O’Hara steps forward with a tangible offer of marriage and a plan to shelter her until the Sydney-bound boat sails, but Sadie declines, choosing her own path rather than dependence or complicity in a risky future.
Later, while native drums beat at a powerful, uninhibited dance, the repressed Davidson, driven by lust, enters her room and proceeds to rape her offscreen amid the rhythmic pounding. The next morning he is found dead on the beach, his throat slit—a suicide that leaves the ship, the island, and Thompson at a moral crossroads. The assault and Davidson’s death expose the hollowness of his hypocrisy and the rigidity of his worldview, and Thompson’s defenses crumble, allowing her to return to the life she once led. She leaves for Sydney with O’Hara to start a new chapter, signaling a hard-won, if troubling, sense of freedom and reinvention.
