In 2010, a probation officer conducts a routine check on 76-year-old Joseph Naso, in Reno, Nevada. During a search of Naso’s home for probation violations, the officer finds a shocking cache of materials: thousands of pictures of women in hosiery, mannequins dressed in lingerie, and a journal recounting dozens of sexual assaults. But the most important piece of evidence found is Naso’s “List of Ten,” a handwritten list with ten cryptic entries of vague locations, but no names or dates. Investigators fear that they have stumbled upon a hidden serial killer and his list of victims completely by chance. Working against time, investigators have one year to decode the list before Naso goes free.