Homicide Detective Avery Black has been through hell. Once a top criminal defense attorney, she fell from grace when she managed to get a brilliant Harvard professor off - only to watch him kill again. She lost her husband and her daughter, and her life fell apart around her.

Trying to redeem herself, Avery has turned to the other side of the law. Working her way up the ranks, she has reached the rank of homicide detective, to the scorn of her fellow officers, who still remember what she did, and who will always hate her.

Yet even they cannot deny Avery's brilliant mind, and when a disturbing serial killer strikes fear into the heart of Boston, killing girls from elite colleges, it is Avery they turn to. It is Avery's chance to prove herself, to finally find the redemption she craves. And yet, as she is soon to find out, Avery has come up against a killer as brilliant and daring as she.

In this game of psychological cat and mouse, women are dying with mysterious clues, and the stakes could not be higher. A frantic race against time leads Avery through a series of shocking and unexpected twists - culminating in a climax that even Avery could not imagine.