A tropical paradise seems like the ideal place for amateur detective Sadie Hofmiller to relax and unwind from the panic attacks that have begun to control her life. But when Sadie accepts the offer to stay at a friend's condo on the island of K'auai, her perfect vacation turns into a nightmare. On a snorkeling trip with the Blue Muumuus, a community group of adventurous older women, Sadie finds herself entangled, quite literally, with the dead body of Noelani Pouha, a local drug addict. The police are convinced they know exactly what happened to Noelani. Reeling from the shock of her own near,drowning, Sadie has no interest in looking for any other possible answers until Noelani's son appears on her doorstep, presenting her with a reason to gather her inner strength, rally her investigative powers, and use what she's learned from her past cases to try and find closure . . . for both of them.