StMU Research Scholars

Featuring Scholarly Research, Writing, and Media at St. Mary’s University

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, (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, (accessed September 5, 2018).
  4. Justin Moyer, “And the Zodiac Killer is…,” The Washington Post, May 14, 2014, (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.

Tags from the story

Arthur Leigh Allen

Robert Graysmith

Zodiac Killer

Recent Comments

Ruben Basaldu

The only thing that I know about the Zodiac Killer is the name and that is mostly through shows on tv but this article is very well written and kept me interested throughout the whole article. What I find interesting is that they had evidence on Allen but it still wasn’t enough to truly prove that it was him and because of his death we will never really get a real answer as to if it was him or not. If it was then the killer is dead but if it wasn’t then the real killer was still on the loose. What a mystery.



5:43 pm

Ava Rodriguez

This is an interesting article, it clarified much more about who he could have been. I remember talking briefly about unidentified serial killers such as Jack the Ripper, and the Zodiac Killer. I have always heard stories about the Zodiac Killer not really knowing what exactly the details were. I had no idea that there was so much evidence, but it still was not enough to pin him. It still remains unresolved, and now that he is dead there really is not much left that could be done.



5:43 pm

Makenzie Santana

I have heard about the zodiac killer only because his name stood out, but never bothered to learn more about him. It is shocking that with the evidence they had on Allen, they never believed it was enough to prosecute him, when they clearly should’ve dug deeper into an investigation on him. It is sad that they were too late on prosecuting him because of his death, but in a way I think of it as he got what was coming to him anyways.



5:43 pm

Maria Garcia

Articles such as this one deeply interest me because of all of the crime shows I watch such as “Criminal minds” and “Chicago P.D.”. The authorities had so much evidence on him, yet still hesitated on whether he was the one who committed the murders. Once they finally felt like he was the one committing the murders, it was too late. All those families were left without justice, and even though he passed away, he should’ve served time for the actions that all seemed to be his.



5:43 pm

Andrew Petri

This article is very interesting and does a great job at writing an attention grabbing story. I have always heard about the Zodiac killer, but never knew what it was about. I am very into crime stories because I really like the show “Criminal Minds”. The images used in the article do a great job at setting the mood for the reader, and the choice of words really gives the article a heavy feeling while reading.



5:43 pm

Stephanie Cerda

I’m a big fan of zodiac killer theories I enjoy seeing what everyone things about this case. It’s interesting to hear all the information backing it up and how it is all connected. Allen does sound like a good victim, however I’ve also heard other theories pointing other people that could also be true! According to some facts that I’ve researched, Allen’s fingerprints and DNA didn’t match the one’s found at the scene. Also, although handwriting analysis isn’t very reliable, I don’t think it matched either. Still, there’s always the chance that was a mistake, and the evidence you mentioned, like his birthday, and his sister, could really mean he was the Zodiac Killer. It’s terrible that the serial killer was never caught, and that the families of the victims never truly received justice. A positive is that people are still learning about it and in that way, their memories are still kept alive.



5:43 pm

Cristianna Tovar

This article convinced me that Graysmith had enough evidence to prove that Allen was the Zodiac killer. For example, people that were close to Allen claimed that he referred to himself as the “Zodiac,” and on December 18th,1969, the Zodiac made a phone call to Melvin Belli’s household and claimed that it was his birthday and that he was going to kill, while Allen’s birthday is on December 19th. However, the case is still unsolved, and there is plenty of more evidence that connects other people to the murders. I think it’s so interesting to hear about all the evidence that’s present in this mystery, and I hope one day that it can finally be solved so that the victims can be brought to justice.



5:43 pm

Vania Gonzalez

So this is a very interesting topic to me because I like to solve things and the Zodiac Killer was one of the toughest serial killers to catch at the time and so I’ve also read into this particular case and I just think its so cool that you really went into the research. These types of cases are always so fun to talk about because of all the possible outcomes that could have come out of it, but it also very sad that the killer was not caught.



5:43 pm

Emmanuel Diaz

I am just amazed by this article. The amount of evidence and detail it goes through and by retrieving so much information and back story is amazing. The fact that Allen called himself zodiac and did things without trying to hide it is just psychotic. He was out there on purpose and had no plans to hide it. So much evidence in his theory that ties it all together but its just a theory. A very compelling and well backed up theory and a coincidence that he hada a heart attack before being tried for the murders of the “Zodiac Killer”



5:43 pm

Michael Lazcano

How scary is it to think that no one ever caught The Zodiac Killer, but his case is also one of the most infatuating in modern history. It’s not Ted Bundy or Ed Gein where we caught and more or less understand why he did what he did, we don’t have an exact idea who he was, why exactly he did what he did, or what kind of person he was. All we know about him is how he killed his victims, and the various letters and notes he sent to the police. The era that he was in definitely gave him an advantage when executing his killings due to the lack of social media, instant information, fingerprinting, etc. Since technology has advanced such events like this are less common and are catchable in the early stages of their killing sprees. The Zodiac Killer was definitely a psychopath who had little to no empathy for humanity, and it’s frightening to fathom what was going through his head.



5:43 pm

1 2 3 4 7

Leave a Reply