Recovering from recent emotional trauma, National Park Service ranger Anna Pigeon goes to New Orleans to visit her friend, Geneva, only to become the target of a dark curse, prompting her to investigate what it has to do with a fugitive mother accused ofkilling her family.

Running from a proposal of marriage from Sheriff Paul Davidson, Anna Pigeon takes a post as a temporary supervisory ranger on remote Garden Key in Dry Tortugas National Park, a small grouping of tiny islands in a natural harbor seventy miles off Key West. This island paradise has secrets it would keep; not just in the present, but in shadows from its gritty past, when it served as a prison for the Lincoln conspirators during and after the Civil War....