The Zodiac Killer was a sadistic serial killer who committed the Zodiac murders in the late 1960s and early 1970s. He has yet to formally be identified, having escaped unapprehended since the murders occurred.

However, there have been a few suspects mentioned over the years. The prime suspect has always been Arthur Leigh Allen, who died in 1992, but a Californian woman is now claiming her father, Guy Ward Hendrickson, was the true Zodiac Killer.

There were five known victims of the Zodiac Killer, but there could be more whose murders are yet to have been linked. The case is an interesting one due to the letters sent by the killer which included ciphers and cryptograms.

This video takes a look at the case in hindsight in a kind of cold case style. Deborah Perez is now claiming her long-deceased adoptive father was the Zodiac Killer, but the jury still seems to be out on whether this is true.