A crime writer digs into the decades-long investigation of a serial killer in California, and finds a growing online community of amateur sleuths trying to solve the case:

“The Golden State Killer, though, has consumed me the most. In addition to 50 sexual assaults in Northern California, he was responsible for ten sadistic murders in Southern California. Here was a case that spanned a decade and ultimately changed DNA law in the state. Neither the Zodiac Killer, who terrorized San Francisco in the late 1960s and early ’70s, nor the Night Stalker, who had Southern Californians locking their windows in the ’80s, was as active. Yet the Golden State Killer has little recognition; he didn’t even have a catchy name until I coined one. His capture was too low to detect on any law enforcement agency’s list of priorities. If this coldest of cases is to be cracked, it may well be due to the work of citizen sleuths like me (and a handful of homicide detectives) who analyze and theorize, hoping to unearth that one clue that turns all the dead ends into a trail—the one detail that will bring us face-to-face with the psychopath who has occupied so many of our waking hours and our dreams.”