Nearly forty years ago, Lux Madigan's twin sister, Nix, vanished from the asylum where they were institutionalized during the Eugenics Movement. Lux is haunted by her disappearance but more by what happened in the moments before. Or at least what she recalls happening. Approaching sixty with a damaged memory and a fatal heart condition, Lux's time is running out. In desperate belief that her sister is still alive, she spends her days searching Cape Perpetua, a city of twins that according to legend was cursed when the Twin Sisters ran ashore in the mid-twentieth century. But the hole in Lux's heart continues to grow and the screams of the child that only she seems to hear are getting louder. With a deadly storm headed toward Cape Perpetua, she must find Nix and beg forgiveness before it's too late. When a letter Lux writes to the editor of the local paper lands in the hands of Victoria Belmont, a widowed journalist who is struggling with a life-changing decision and ghosts from her own past, the atrocities of the Eugenics Movement are brought into the light. Determined to find out what happened to the missing girl because of a personal connection to the asylum, Victoria will first need to discover what happened to Lux and solve the mystery behind her strange fugues and the numbers carved into her wrist. As memories resurface and long-buried secrets are unearthed, both women must come to terms with who they are and what they have done. They must remember in order to forget.