When the clipper ship The Golden Bough docks in San Francisco, its crew hurries to escape their cruel master, Captain "Black Yankee" Angus Swope. As has happened many times before, the captain reaps the benefits when his crew leaves before claiming their pay, and the waterfront quivers under the news that Swope's "hell ship" is seeking another crew. Swope's daughter Mary also goes ashore, ostensibly to go shopping, but in reality to escape her father, who plans to marry her to his brutal first mate, Fitzgibbons. In San Francisco, Mary meets a young sailor, John Shreve, who saves her from the lascivious attentions of "The Rat," who is the henchman of "The Knitting Swede," a notorious shanghaier of reluctant sailors. John takes Mary to a respectable boardinghouse, but she is followed by Swope and taken back to the ship. To be with Mary, John signs on with Fitzgibbons. John is joined by his new friend, Newman, who has a mysterious personal motive for voluntarily signing on to serve under the infamous Swope. The rest of Swope's crew is made up of men shanghaied by the Knitting Swede, and includes Deaken, a minister who has been trying to end the Knitting Swede's practices; a huge Swede named Eric; Snowflake, a black sailor; and the Rat. On board the ship, Newman confronts Swope. Swope is terrified to see him, for Newman was once the skipper of The Golden Bough , and Swope was his envious first mate. Swope framed Newman, and after he was sent to prison, stole his ship, wife and infant daughter. Newman's wife died from Swope's mistreatment, and Swope then raised the child, Mary, as his own. After bitterly languishing in prison for fifteen years, Newman has come to seek his daughter and revenge. Before the matter is resolved, however, Swope finds John and Mary in each other's arms. A fight ensues, which John almost wins, but with the help of Fitzgibbons, Swope almost kills the young sailor. Swope then accuses Newman of mutiny and puts him in the ship's brig. He threatens to hang his rival as soon as Mary and Fitzgibbons are wed, but John recovers and plans a rescue. Eric releases Newman, and the trio goes to the captain's cabin to do battle with Swope and his men. After Eric throws Fitzgibbons overboard, Swope is placed in irons. Newman then reveals his true identity, reunites with his daughter and takes back the captaincy of his ship. Under Newman's beneficent leadership, the vessel heads out to sea, and Mary and John look forward to a new life filled with happiness.