When a young South Seas sailor falls overboard, the beautiful daughter of a Polynesian king dives in and saves his life. Thus begins the romance of Johnny (Joel McCrea) and Luana (Dolores del Río). Though Luana is promised to another man, Johnny whisks her away, and for a brief time the lovers live very happily together. But, when a local volcano threatens their lives, Luana knows that she must sacrifice herself to the volcanic gods in order to save her island.