Netflix’s This is the Zodiac Speaking offers a new perspective on one of the most notorious unsolved killing sprees in history. More than six decades have passed since the San Francisco Bay Area was terrorized by an elusive killer, whose identity remains unknown despite years of investigation. The self-proclaimed Zodiac Killer has been linked to five murders that took place between 1968 and 1969, though he is said to have claimed responsibility for more than 30 murders. The killings are regarded as one of America’s most infamous cold cases and raise questions about whether the perpetrator is still at large.

The serial killer is infamous for taunting investigators, with The Zodiac sending a series of coded cryptic letters signed with a crosshair symbol. Between 1969 and 1974, four ciphers were sent to newspapers across California, with two ciphers remaining unsolved to this day. Since his final cipher in 1974, police and investigators have been searching to determine the identity of the Zodiac Killer and whether he is still alive today.

The Zodiac Killer Is Likely Already Dead

The Lead Suspect Died In 1992

The three-part This Is The Zodiac Speaking documentary examines the Seawater family and their relationship with a schoolteacher named Arthur Leigh Allen, the main suspect in the Zodiac Killings. In an interview with TIME, the family talked about how Allen allegedly brought them to locations where the killings took place, and claimed that he confessed that he was the Zodiac Killer to them before his death in 1992. Despite being the prime suspect, investigators were never able to connect Allen to the killings. However, new evidence was presented in the Netflix Zodiac documentary, that offers a fresh insight into the case.

Since Allen’s death in 1992, other suspects have been identified in the killings. According to Stylecaster, podcasts and authors have identified Gary Francis Poste, Earl Van Best Jr, Ross Sullivan, and Louis Joseph Meyers as potential suspects, but none of these men are alive today. If the killer was in his late 20s when he began his killings, he could possibly be still alive as he’d be in his late-80s today, but as there is no official identity for the Zodiac Killer, it’s more than likely that he is also dead.

How Old The Zodiac Killer Was Thought To Be In The Late 1960s

The Killer’s Appearance Was Never Fully Determined

One of the reasons why the Zodiac Killer was never caught, was because his physical appearance was never fully determined by investigators. In the original composite sketch released in 1969, the killer was described as a white male, aged around 35 years old (via ForArtist). He was further described as standing around 5″10 tall, had a medium build, wore horned glasses and dark clothing (via Criminal Minds). However, this description has since been disputed by survivors and eyewitnesses.

The contracting descriptions make it difficult to determine the true age of the Zodiac Killer.

One survivor, Michael Magou, later described the killer as a pot-bellied white man, standing 5″8 tall and heavy. In This Is The Zodiac Speaking, three witnesses to the murder of Paul Stine in 1969, gave a description of a husky-looking man who wore black clothing. The contracting descriptions make it difficult to determine the true age of the notorious criminal. Without any confirmation of his age and identity, it remains uncertain if the Zodiac Killer is still alive today.