Sarah Booth Delaney's fianc, Graf Milieu, has become depressed while recovering from a severe leg injury, but Sarah Booth knows just how to help him heal. She's arranged a romantic getaway for the two of them at a lovely beach cottage on Dauphin Island off the Gulf Coast. On the first day of their island adventure, they take a historical tour led by Angela Trotter, a young woman well-versed in local lore, including rumors of pirate treasure hidden somewhere on the island. In fact, Angela confides to Sarah Booth and Graf that her father, a sailor and treasure hunter, was murdered just when he thought he was closing in on the treasure. Angela's convinced that the wrong man was imprisoned for her father's murder, and she manages to persuade Sarah Booth to take the case.