A female serial killer is on the loose, and it's up to FBI agents Dillon Savich and Lacey Sherlock to track her down. There's evidence that the woman, Kirsten Bolger, has a killer bloodline, too: a connection to the notorious Ted Bundy only complicates the case. At the same time, Special Agent Lucy Carlisle learns from her dying father that her grandfather hadn't simply walked away from his family twenty-two years earlier: he had, in fact, been murdered by his wife, Lucy's grandmother.