After a roustabout sailor avoids being shanghaied in 1850s San Francisco, his audacity helps him rise to a position of power in the vice industry of the infamous Barbary Coast.

In 1834, Charles Stewart (Alan Ladd), the spoiled, dissolute son of a shipping magnate, is shanghaied aboard the Pilgrim, one of his father's own ships. He embarks upon a long, hellish sea voyage under the tyrannical rule of Captain Francis Thompson (Howard Da Silva), assisted by his first mate, Amazeen (William Bendix). One of his crewmates is Richard Henry Dana Jr. (Brian Donlevy).

Incompetent door-to-door vacuum cleaner salesmen become enlisted without their knowledge.

After being shanghaied in a plot to have him declared dead and take over his ranchero and other properties, Don Ricardo, disguised as a peon, returns to Old California, and begins the fight to reclaim what is his.