9 "Criminal Minds" Episodes That Are Based on Very Creepy True Stories

One of the long-running nemeses to the BAU is the "Boston Reaper," a serial killer who began his spree in the 1980s and whose cold case was one of Agent Aaron Hotchner's earliest investigations. The killings are designed to bear a striking similarity to the Zodiac Killer, one of the most famous cold cases in American history. Both carried out a string of brutal murders, both taunted law enforcement over their inability to catch the culprit, and both got away with their crimes for years. This being a TV show, though, the "Criminal Minds" killer eventually is defeated, while the real Zodiac case remained unsolved until a breakthrough in late 2021.