Paul Holes, retired from the Contra Costa County District Attorney’s Office, relates the chilling story of the case that dogged him for over 20 years—the notorious Golden State Killer, who committed over 100 burglaries, more than 50 rapes and at least 13 murders from 1974 to 1986. Ultimately, Holes solved the case in collaboration with a genetic genealogist, using the relatively new—and controversial—technique of forensic genetic genealogy (FGG) or investigative genetic genealogy.