No One You Know

Twenty years ago, Ellie Enderlins sister, Lila, a brilliant mathematician, was murdered in a crime that was never solved. In the aftermath of her sisters death, Ellie entrusted her most intimate feelings to a man who turned the story into a bestselling true crime booka book that both devastated her family and identified one of Lilas professors as the killer. Decades later, Ellie receives a piece of evidence never found with her sisters body: a notebook of Lilas filled with mathematical formulas. It will lead her to a hundredyearold mathematical puzzle, to a lover no one knew Lila had, to the motives and fate of the man who profited from their familys anguishand to the deepest secrets even sisters keep from each other.