Martha's Vineyard has been home to Victoria Trumbull for most of her ninety-two years. Its magic, history, and picture-perfect calm are part of her very being. But one evening, Victoria hears something that doesn't quite belong: a scream followed by a splash and a sound of a car speeding away. She investigates and discovers a body on the outgoing tide. Victoria concocts a scheme to trap the killer, but she'll need to act quickly-victim number two has just been found.