An obsessive quest to solve the mystery of her older sister's disappearance puts a young woman in mortal jeopardy in this taut, sophisticated novel of psychological suspense from the author of the "truly riveting" ( New York Times) The Book of You. An intoxicating cocktail of loyalty and secrets, lies and betrayal, reminiscent of Rosamund Lupton's Sister and Kimberly McCreight's Reconstructing Amelia. A decade ago, Ella Brooke's older sister, Miranda, vanished without a trace. With every passing year, Ella has come to resemble more closely the sister she lost—the same dark hair, the same piercing blue eyes—and now she's the same age Miranda was when she disappeared. Ella has never let go of her sister. She can still feel Miranda's presence, still hear her voice. She still talks to her. What holds Ella together is her love for her sister's ten-year-old son and her work as a self-defense expert helping victims. Ella is certain that Miranda was taken, and that one man is key to her disappearance: Jason Thorne. The tabloids report that a new link has been found connecting Miranda to this sadistic serial killer locked away in a psychiatric hospital. Ignoring warnings from the police and the disapproval of her parents, she seeks Thorne out. Ella will do whatever it takes to uncover the truth—no matter how dangerous…