In the Prologue, McNamara describes how she became involved in researching the Golden State Killer, a serial rapist and murderer attacking individuals in California in the 1970s and 80s. McNamara first begins writing about unsolved crimes in 2006, when she launches her blog True Crime Diary. McNamara conducts internet research about unsolved crimes and writes about her discoveries. In 2012, McNamara begins investigating a criminal she names the Golden State Killer (GSK). The criminal rapes a series of women in the 70s in Northern California, before later committing a series of murders in the 80s in Southern California. Many of the crimes were originally thought unrelated until DNA evidence proves that a single man committed the crimes. However, detectives have never been able to identify the culprit. McNamara obsessively investigates the GSK, searching for any evidence that might point to the killer’s identity. She begins to search for “items of personal value” that the killer stole from his victims after raping them (3). One evening, McNamara discovers a rare pair of cufflinks for sale on a vintage store’s website, identical to cufflinks that the GSK stole from a woman he raped in Stockton, California, in September 1977.