The Zodiac Killer was a serial killer who operated in Northern California during the late 1960s and early 1970s. The killer was responsible for at least five documented murders, as well as other violent attacks, and famously communicated with the media and police through a series of cryptic letters and messages. Despite the investigation of numerous suspects, no one seems to be definitively linked to the crimes. The case remains one of the most notorious unsolved mysteries in American history. The Zodiac Killer's elaborate codes and cryptic messages to the media and police have captured the public's imagination and fueled endless speculation about the killer's identity and motives