California: 13 murders, 50 assaults, 42 years of investigation.

In 2018, police announced that they had finally arrested the "Golden State Killer," a man responsible for over 140 burglaries, 50 rapes, and at least 13 murders committed in California throughout the 1970s and ’80s. William Thorp dives into this case, exploring the dark side of sunny California, the innovations in forensic science that made solving it possible, and the real inside story of an amateur sleuth who dedicated the last years of her life to understanding how one of the country’s worst criminals could have gone undetected for so many decades.