Sheldon Woods kidnapped and killed an untold number of boys, then escaped the death penalty by making a plea deal for multiple life sentences. Nearly a decade later, the full extent of his crimes is still unknown, and many of his victims have never been accounted for. But Lisa Walsh is certain her brother Christopher was one of them—and to honor her mother's dying wish, she's on a mission to learn the truth and recover the lost little boy's remains. FBI agent Portia Cahill is tasked with confronting the caged killer, and obliged to play his mind games to get what she's after. But she ends up with more than she bargained for when the remains of another boy's body are discovered.

Determined to ID the mystery child, Portia reluctantly teams with James Doyle, the attorney who once defended Woods. But chasing a killer's grisly legacy, and the bones of the forgotten dead, will lead them into the lethal orbit of a latter-day monster who's seeding the graves of the past with a fresh wave of innocent victims.