Ruth Hoagland grows up on the Florida Keys with no companion other than her father, a half-witted fisherman who spends most of his time hunting for buried treasure. Vacationing yachtsman Bob Winthrop and Ruth fall in love, but Winthrop returns to New York, and after a year, has forgotten Ruth. After finding two chests in a cave, Ruth locates her father unconscious from a fall. She goes to the mainland for help, but returns with the Reverend Josiah Arbuthnot and Dr. William Strong, to find her father dead. Strong, out of kindness, offers to marry her, but Ruth declines, sure that Winthrop will return.