A woman arrives in San Francisco during the gold rush, works for a crooked casino boss, and falls in love with a poetic prospector.
Mary Rutledge (Miriam Hopkins) arrives in San Francisco and is assisted ashore by the generosity of Cobb (Frank Craven) despite the greed of Old Atrocity (Walter Brennan). She came to marry a millionaire; but he was killed after losing his gold gambling. At the Bella Donna saloon and casino she meets owner Louis Chamalis (Edward G. Robinson), who enters her room without knocking and offers her a job working the roulette wheel. The mayor and his wife snub Mary, but Louis gets revenge by buying everything in the store. Sawbuck McTavish (Donald Meek) loses several bags of gold; when he complains, Louis has Knuckles (Brian Donlevy) knock him down. When Ferguson threatens to expose the crooked game, Knuckles shoots him dead. The sheriff arrives to arrest knuckles; but Louis gets a drunk judge to give him a trial in the casino. The judge rejects a Chinese witness and dismisses the case. Knuckles cuts off Ah Wing's pigtail.
Citizens ask Cobb to print the truth about Chamalis, who orders his men to smash the press. Mary objects, and Louis only damages the type, warning Cobb. Mary asks Louis why he murdered; he says it was business and demands she love him, threatening her. Mary rides in the rain and meets Jim Carmichael (Joel McCrea) in a cabin. While her clothes dry, he says he is leaving with his gold; he talks and acts like a poet, giving her a poetry book. His ship delayed by fog, Old Atrocity takes Jim to Bella Donna for dinner where he sees Mary working and is disillusioned. He loses his gold and is knocked out by a drink Knuckles gave him. Mary cries in her room, refusing to see Louis. Jim wakes up and asks Louis for a job. He shines spittoons and waits on Mary. She offers him fare to New York, but he declines. When Cobb refuses to print his story, McTavish puts up a poster. Knuckles shoots McTavish and Cobb, tearing down the poster. Cobb, dying, tells Wigham to print the story for the sake of law and order.
Citizens help Wigham distribute the newspapers. Louis asks Mary about the poetry book. Vigilantes arrest, try, and hang Knuckles. Old Atrocity gives Jim a bag of gold he lost, and Jim says good-bye to Mary. She has him gamble, and he wins $40,000. Men sign up as vigilantes to get Chamalis. Louis learns they lost money and goes after Jim, locking Mary in her room. Jim is there and says he loves her. She goes with him out the window. While vigilantes break up the saloon, Louis follows Mary and Jim in a boat. Jim is wounded. Mary promises to love Louis if he'll let Jim live. Louis tells his men to put Jim on the ship, as Mary cries. Louis realizes that Mary loves Jim. Vigilantes arrest Louis, and Mary goes on the ship.
This story explores the dangers of lawless society when violence and greed dominate. Citizen action, crude at first, manages to bring about a rough justice. A woman traveled far to marry money but realizes a poetic man is better.