A true-crime masterpiece written by a cold-case-cracking master. Barbara Rae-Venter's investigative DNA work has revolutionized the way law enforcement hunts serial killers. For twelve years the Golden State Killer terrorized California, stalking victims and killing without remorse. Then he simply disappeared, for the next forty-four years, until an amateur DNA sleuth opened her laptop. In I Know Who You Are, Barbara Rae-Venter reveals how she went from researching her family history as a retiree to hunting for a notorious serial killer-and how she became the nation's leading authority on investigative genetic genealogy, the most dazzling new crime-fighting weapon to appear in decades.