A cold case heats up when a 9-1-1 call puts police at a Denver murder scene pointing investigators to the abduction of a Colorado teenager fourteen years before. The connection? A calling card—a single black pearl—is found on the newest victim. Is the murder a copycat? Or has a twisted serial killer, thought dead or in prison, returned to kill again? The hunt for a multi-state killer is on and brings together an unexpected team: a Denver Major Crimes police lieutenant; an FBI special agent who investigated the previous murders, a rookie FBI agent with a specialty in psychology; and the only living victim of the Black Pearl Killer is now a cop. For Special Agent Brian DiPietro, the case is an opportunity to find answers. For Officer Allison Shannon, the case will force her to face down the town that blamed her for surviving when another did not. And for both DiPietro and Shannon, it’s a chance to find closure to questions that have tormented them both for years.

This killer won't stop …until she's dead When Lt. Everett T. Pope is notified of an explosion in downtown Denver close to the judicial buildings, his first instinct is gas leak. No such luck. As Incident Command and Pope's own Major Crimes unit move in, he discovers he knows the intended victims—an Assistant U. S. Attorney—and Pope's former partner, now a private investigator, has died shielding the injured AUSA with his body. As ATF and the FBI take over investigating the bombing and unraveling motives behind the murder attempt, Pope is relegated to a peripheral role. But the injured AUSA's aunt is a United States senator used to getting results. She turns to the team that solved the Black Pearl Killer murders with a very big ask—find her answers and locate the bomber. FBI Special Agent Brian DiPietro must recall his entire cold case team from their far-flung assignments knowing he's being asked to do the impossible. The senator, however, doesn't know the meaning of the word. All too soon, DiPietro finds his team working alongside ATF on a red-hot mission. One that uncovers a decades' old cold case.