Fifteen years ago, four families, across three states, were brutally murdered in their homes. It took sixteen months for a team of federal agents to capture the serial killer responsible. For over a decade, Elijah Barone has been serving multiple life sentences in a maximum-security prison, bringing relief across the country and closure to the victims' loved ones. Former FBI consultant Brooklyn Sloane needs a distraction from her life, both personally and professionally. In search of a much-needed break, she agrees to teach a class on criminal profiling at a local university. It is during a class assignment on successfully closed cases that the light is shined on the truth. Elijah Barone is a cold-blooded killer, but he isn't responsible for killing the Knox family, which means another killer is still stalking from the shadows. The brutality of the murders leaves Brook unable to walk away from the case. But as she looks deeper into the past, the killer's identity all points back to someone who belongs to the Knox family. Brook knows all too well that family secrets can't remain buried. She, alongside her team, won't stop until the killer is brought to justice. Only this killer knows how to remain hidden—and he'll do whatever is necessary to silence the truth.