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November 3, 2018

The Unsolved Mystery of the Zodiac Killer

Winner of the Fall 2018 StMU History Media Award for

Best Article in the Category of “Crime”

Best Article in the Category of “Political History”

Robert Graysmith, a cartoonist working for the San Francisco Chronicle in 1969, developed an obsession to discover who the Zodiac Killer was. On a rainy night he received an image of a driver’s license of a man named Arthur Leigh Allen. On this license was Allen’s date of birth, December 18, 1933. This information became the final clue in Graysmith’s investigation, allowing him to put all the pieces together to discover the identity of the Zodiac Killer.

On August 1, 1969, the first letter written by the Zodiac Killer was delivered to the San Francisco Chronicle. The letter was a confession to the murder of two teenagers, Darlene Ferrin and Michael Mageau, on July 4, 1969, at Blue Rock Springs Park in Vallejo, California.1 A cypher was attached to the letter and the killer demanded that his cypher and letter be published in the newspaper, threatening to kill more if the paper did not do so. This letter and the cypher that came along with it was the initial spark that led Graysmith into his obsession with finding out who this Zodiac Killer was. He himself tried to decode the cypher by reading different books involving code breaking, but was beaten to solving it by Donald and Bettye Harden, who solved the code themselves. Within the cypher, it talks about “man [being the most] dangerous animal of all.”2 Graysmith discovered that this line was from the movie The Most Dangerous Game, which is about a man who hunts people for sport. Nonetheless, this became Graysmith’s first piece of evidence to be discovered from the Zodiac Killer’s letter; yet, it wasn’t until seven years later, in 1977, when Graysmith started adding up the evidence that would pointhim to Arthur Leigh Allen as the Zodiac Killer.

Darlene Ferrin murdered by Zodiac Killer and Michael Mageau who was wounded by him July 4, 1969 (Blue Rock Springs Park. Vallejo, CA) | Courtesy by Wikipedia

Arthur Leigh Allen had a friend named Don Cheney, who provided information that pointed to Allen as the prime suspect in the investigation. Cheney had mentioned that on “September 27, 1969 in Napa, California, Allen [had told his family] he’d be leaving for the afternoon to go scuba diving at Lake Berryessa.”3 However, later that day Allen returned home covered in blood with a bloody knife found in his car. That same day a police report was filed for one murder that involved the killing of Cecelia Shepard, age 22, and although Bryan Hartnell was a victim in the attack that killed Shepard, he was able to survive. 

Image of Zodiac Killer in his “murder suit” killing Cecelia Shepard and Bryan Hartnell | September 27, 1969 (Napa, CA) | Courtesy of Wikipedia

Allen’s same friend, Don Cheney, also confessed that Allen referring to himself as the “Zodiac” before the publication of the letters, and even before the murders had taken place. Allen not only referred to himself as “Zodiac,” but also wore a Zodiac brand watch. The police further investigated him by searching his trailer, but “only [found] small dissected animals, bloody knives and sexual devices.” 4 None of this, however, was direct evidence linking Allen to the murders. Although he was not convicted for murder, he was separately convicted of child molestation resulting in a three year sentence in prison. Coincidentally, no Zodiac letters were sent during this time to the San Francisco Chronicle. Additionally, during his time in prison, one of Allen’s inmates reported to the police a confession Allen had told him. Allen reportedly took responsibility for the murder of Paul Stine, a taxi driver who was shot in the head by his passenger. This murder was also mentioned in one of the Zodiac’s letters. Right after this incident, an interview on national television by Melvin Belli had tried to elicit a confession from Allen for the murders, but unsuccessfully. Afterward, the Zodiac Killer tried to reach out to Belli by calling his house on December 18, 1969. Belli was unable to answer, but his maid did. She stated that all the Zodiac Killer said was, “It’s my birthday, I must kill.”5 A chilling, yet important fact in the investigation.

Letter to call himself the Zodiac Killer including his signature mark | August 1, 1969 | San Francisco, CA | Courtesy of Wikipedia

One piece of evidence that seemed to sealed the deal for Graysmith that Allen was the Zodiac Killer was Graymith’s interview with Linda Ferrein. Graysmith sought to question Darlene Ferrin’s sister, Linda Ferrin, to find out whether there was any correlation with her sister and the Zodiac Killer, due to a piece of information referencing Darlene’s painting parties in one of his letters. As Graysmith interviewed Linda, she described Darlene as always being surrounded by boys. But there was one in particular who stood out to her. Linda described this boy as antisocial when he attended one of Darlene’s painting parties. Darlene also warned Linda to stay away from him because she said he scared her, and also mentioned to her sister that this was the same man who confessed to her he had killed someone. Not only that, but he had a nickname for himself, which was Leigh, which was also Allen’s middle name. During that same time, Graysmith received an image of Allen’s driver’s license confirming Allen’s date of birth, December 19, 1933, the same date on which he made a phone call to Melvin Belli stating, “It’s my birthday, I must kill.”6 All of this piled up evidenced convinced Graysmith that Allen was the Zodiac Killer, because this was the only time that the Zodiac Killer gave out a piece of personal information. Unfortunately, authorities planned to have a meeting charging him with all these murders, but Allen suffered from a heart attack before the meeting could take place. 

Image of Arthur Leigh Allen’s driver’s license | San Francisco, CA | Courtesy of Wikipedia

Convincing enough? This is one of the most popular theories from Robert Graysmith who believed the serial murderer was Arthur Leigh Allen. Although there is supporting evidence that points towards him as the killer, many question Graysmith’s judgment and overall investigation. Regardless, the case still remains unsolved and we may never know who the real Zodiac Killer was. Was it Arthur Leigh Allen or was Graysmith’s theory further off than we thought?

  1. William Booth, “The Zodiac Writer,” The Washington Post, Mar. 09, 2007, http://www.washingtonpost.com/wp-dyn/content/discussion/2007/03/09/DI2007030900522.html (accessed September 5, 2018).
  2. Robert Graysmith, Zodiac (Penguin Publishing Group, 2007), 78.
  3. William Booth, “A Killer Obsession,” The Washington Post, Mar. 1, 2007, http://www.washingtonpost.com/wpdyn/content/article/2007/02/28/AR2007022801979.html (accessed September 5, 2018).
  4. Justin Moyer, “And the Zodiac Killer is…,” The Washington Post, May 14, 2014, https://www.washingtonpost.com/news/morning-mix/wp/2014/05/14/and-the-zodiac-killer-is/?utm_term=.28c06c343598 (accessed September 7, 2018).
  5. Robert Graysmith, Zodiac unmasked (New York: Berkley Books, 2003), 180.
  6. Robert Graysmith, Zodiac unmasked (New York: Berkley Books, 2003), 180.

Nathalie Herrera

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Recent Comments

125 comments

  • Emily Jensen

    I really enjoyed reading this article, a great addition to the crime genre for the website. The zodiac killer remains a mystery to us to this day, a fascinating story of a killer who managed to avoid the police; or so I had thought before reading. The evidence that this article presented was thoroughly researched and well organized, overall a great read!

  • Diego Aguilera

    It’s unbelievable how Allen’s friends are the ones who turned him. But this case will be a mystery im always interested in because these are my favorites. Another killer story thats my favorite is jack the ripper! well told article and very descriptive with a lot of facts to help the reader understand

  • Madeline Torres

    The Zodiac Killer has always been very interesting to me because it’s by far one of the greatest mysteries in US history. The article was very well written and I enjoyed the amount of detail included. It really made me want to keep reading. There are many theories when it comes up to this notorious killer and it would be amazing for this case to be solved one day. These victims deserve their justice.

  • Lamont Traylor

    I love this article mainly because I find serial killers to be pretty interesting. Not because of what they did but I always want to know what made them do what they did. Other killers like cult leader Charles Manson or Jim Jones must have had some pretty messed up things going through their heads. Also, the school shooters of Columbine had an interesting story on why they did the sick things that they did.

  • Sebastian Carnero

    I wasn’t expecting that a cartoonist would be the closest person to find who was the famous Zodiac killer. It is worth noticing that Graysmith didn’t give up even though putting the pieces together took more than 7 years. Allen seemed to be a very disturbed man, he was obsessed with killing and telling people about it. He wasn’t charged, but he at least went to prison.

  • Caden Floyd

    Unsolved mysteries have always grabbed my interest because it leads to so many possibilities and theories on the truth. Allen really surprised me because it seemed as if he was trying to get convicted as the Zodiac Killer. In my opinion all the signs point towards him and the murders even stopped once he was no longer in the picture. However, maybe that is what the real killer wanted so he could have a clean slate, no one will ever know for sure. This article was very interesting and entertaining to read.

  • Antoinette Johnson

    It is disappointing that we are still unsure if Allen Leigh was the Zodiac killer. I’m glad that they put him in jail for molestation. Graysmith used his ambition and obsession to try to link clues together to figure if Allen was the zodiac killer. It seems possible because the letters stopped when Allen went to prison and the weird call he made saying it is my birthday I must kill. There are still several suspicions in the case, but for the most part Allen was not innocent and is gone forever not to hurt anyone.

  • Robert Freise

    This article had a very nice finish to end. The articulate details in which how the author informed us about the zodiac killer. Loved the imagery and the ways of telling how people would actually try to find the the zodiac killer. The evidence scenario is really crazy to me do to the circumstances in the crime. The way his friends sort of betrayed him do to the exposure of the evidence to the authority’s is weird to to think how close he was to them.

  • Crystal Baeza

    The Zodiac will always be an unsolved mystery people will be interested in. It’s unbelievable how Allen’s friends are the ones who turned him. I’m glad they didn’t want to be the “good friend” trying to cover up evidence but instead helped out the police get closer to closing the case. I find it crazy after all the evidence and theories, the case still remains open and unsolved.

  • Valeria Perez

    I have always found the Zodiac Killer one of the most interesting unsolved mysteries. Why would he kill all of these people? Was it for attention? Did he want to get caught as he left little traces of evidence? What was the San Francisco Chronicles readers’ reaction when they saw the first letter published? I just have a lot of questions regarding this infamous killer.

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