The childhood murder of Lydia Strong's mother has turned her into a woman obsessed with bringing brutal killers to justice. The reclusive, bestselling true-crime writer and investigative consultant has made a life out of chasing monsters. And her powerful intuitions rarely fail her.

When three adults—loners, drifters—go missing, no one seems to notice except for Lydia. Enlisting the help of her friend, former FBI agent Jeffrey Mark, Lydia starts an investigation of her own. But when someone raises the stakes and goes after Lydia—just as fifteen years ago when she put the FBI on the trail of her mother's killer—the real hunt begins.