One killer was bad enough. After famously stopping a serial killer, a detective makes a disturbing discovery: a dark website for serial killers has targeted him. Summoned to a mysterious meeting, detective Cade Dawkins is confronted with his past. A University of Minnesota computer science professor has discovered a disturbing website on the dark web. Made up of serial killers, they use the site to share exploits, brag and offer challenges to one another. But it gets worse. After Cade famously stopped a serial killer in the Twin Cities-and nearly lost the two women closest to him-a new site-wide challenge is issued: Come to Minnesota and outsmart the detective who stopped the Blonde Killer. Come and kill. With two killers from the site terrifying the public, the media turning on him and the governor threatening to fire him, time isn't Cade's friend. But then, neither are the serial killers.