Warning: This article discusses violence and murder.

As explored in Netflix's Zodiac is believed to be responsible for at least five confirmed homicides, though some speculate the actual number could be much higher. The killer's chilling ability to elude law enforcement and his penchant for taunting authorities through cryptic letters only added to the fear he instilled in the Bay Area community.

As the mystery deepened, numerous Zodiac suspects emerged, yet none have definitively been proven guilty, leaving families and investigators searching for answers. The release of Netflix’s documentary has reignited interest in one of the most infamous suspects, Arthur Leigh Allen. While police named him as a primary suspect decades ago, the case remains unsolved, and the list of potential perpetrators continues to grow. From individuals with questionable backgrounds to those simply caught up in the media frenzy, many have been accused over the years.

8 Arthur Leigh Allen

Allen's Alibi and Defense

Arthur Leigh Allen remains the only suspect officially named by police in the Zodiac Killer investigation. A convicted sex offender and former elementary school teacher, he faced accusations of sexual misconduct that led to his dismissal in 1968. Allen's proximity to the crime scene of the first Zodiac victim, Darlene Ferrin, raised suspicions. Despite surviving Zodiac victim Michael Mageau identifying him in a photo lineup, conflicting witness testimonies, including one stating Allen was significantly heavier than the killer, prevented law enforcement from charging him.

This discovery reignited interest in Allen as a potential perpetrator, yet it wasn't enough for a conclusive identification.

Following Allen's death in 1992, a search of his home yielded compelling evidence, including a Zodiac Sea Wolf wristwatch bearing the same logo found in the killer's letters. This discovery reignited interest in Allen as a potential perpetrator, yet it wasn't enough for a conclusive identification. Despite extensive investigation and the circumstantial evidence linking him to the case, Arthur Leigh Allen was never officially charged with the Zodiac murders, leaving his status as only a potential suspect.

7 Gary Francis Poste

Zodiac Cipher Cracked: Poste's Link

In 2021, a group known as The Case Breakers claimed to have solved the Zodiac Killer case, identifying Gary Francis Poste as the culprit. This team of ex-journalists, military intelligence personnel, and law enforcement professionals argued that Poste’s violent history and a unique connection to a sixth murder bolstered their claims. They further alleged that clues within the Zodiac's ciphers pointed to Poste, with former Army counterintelligence agent Jen Bucholtz stating to Fox News, “So you’ve got to know Gary’s full name in order to decipher these anagrams. I just don’t think there’s any other way anybody would have figured it out.”

Despite The Case Breakers’ assertions, Poste was never charged with the Zodiac murders during his lifetime, as law enforcement had no concrete evidence linking him directly to the crimes. He ed away in August 2018 at the age of 80 due to sepsis and vascular dementia. While the group's findings have reignited interest in Poste, law enforcement has yet to officially recognize their conclusions, leaving the case as elusive as ever.

6 Earl Van Best Jr.

Zodiac Suspect: Earl Van Best Jr.

Earl Van Best Jr. emerged as a suspect in the Zodiac Killer case primarily due to accusations from his son, Gary Stewart, and daughter-in-law, Susan Mustafa. They noted a striking resemblance between Van Best and the police sketch of the killer, as well as a partial DNA and print match. However, private investigator Zach Fechheimer later revealed that Stewart had manipulated a police report, claiming Van Best was in Europe during some of the killings. Despite the familial accusations, the evidence against Van Best remained tenuous and unsubstantiated.

Van Best Jr. had a criminal history that included statutory rape, serving time for marrying a 14-year-old, and other offenses. He died in Mexico in 1984, and while Stewart's 2014 book, The Most Dangerous Animal of All, alleged his father was the Zodiac, critics pointed out flaws in his investigation. Forensic evidence did not the connection, with handwriting, fingerprints, and DNA failing to match the Zodiac's. Ross Dinerstein, who worked on a documentary based on Stewart’s book, stated, “I don’t think we’re ever going to know who the Zodiac Killer is. I would be surprised if Earl Van Best Jr. is the Zodiac, but I also wouldn’t be surprised if Earl Van Best Jr. was involved or had some connection to it.”

5 Ross Sullivan

The Case Against Ross Sullivan

Ross Sullivan, a library assistant at Riverside City College, became a suspect in the Zodiac Killer case largely due to his resemblance to police sketches of the murderer and his suspicious absence following the murder of Cheri Jo Bates. Despite these connections, there was insufficient evidence linking him to the killings. Sullivan had been hospitalized for bipolar disorder and schizophrenia, and although he worked in the same library as Bates and knew her, police stated he had an alibi, leading them to rule him out as a suspect.

Sullivan's height of 6'2" also raised questions; eyewitness s varied, estimating the killer’s height between 5'8" and 5'10", which his ers attribute to perception issues.

However, fingerprints taken from library patrons, including Sullivan, were checked against evidence from the crime scene, and no match was found. Additionally, no signs of injuries consistent with a struggle were observed on Sullivan in the aftermath of Bates’ murder, undermining claims of his guilt. Sullivan died in 1977 at age 36, with his suspected ties to the Zodiac case remaining largely speculative.

4 Louis Joseph Myers

The Myers Zodiac Case: Investigation

Louis Joseph Myers emerged as a suspect in the Zodiac Killer case after his friend Randy Kenney claimed Myers confessed to the murders while dying of cirrhosis in 2001. Kenney reported that Myers said, "I killed some people. I'm the guy [they're] looking for." He also alleged that Myers targeted couples out of anger from a failed relationship. However, the only tangible evidence ing this claim is the absence of Zodiac letters during the time Myers served in the military abroad from 1971 to 1973.

Kenney stated that Myers was about 17 years old when the Zodiac's killing spree began and he also alleged that the Zodiac's crosshairs symbol was actually a Celtic cross, and that authorities misinterpreted clues in the killer's communications. “The Halloween card said 'look for a teen,'" Kenney told ABC Fresno. "Alright? And at that time the authorities just thought it meant 14 victims. But it meant 'look for a teen.'” Despite these allegations, law enforcement officials are doubtful of Myers’s guilt as he was never charged before his death.

3 Paul Alfred Doerr

Doerr's Zodiac Connection: The Claim

Paul Alfred Doerr has emerged as a suspect in the Zodiac Killer case, primarily due to claims made by author Jarett Kobek in his book How to Find Zodiac. Kobek notes that Doerr wrote a letter to a sci-fi magazine expressing frustration with the postal service and suggesting the use of one-cent stamps for protest. Interestingly, one of the Zodiac's letters, postmarked around the same time, was sent with six one-cent stamps. Additionally, Doerr self-published magazines featuring ciphers inspired by J.R.R. Tolkien and provided bomb-making instructions that mirrored details found in a Zodiac letter.

Despite these connections, Doerr was never formally investigated by police. He ed away in 2007 at the age of 80. Military records showed no evidence of his claims of foreign service during World War II or the Korean War. Furthermore, his daughter Gloria reported that Doerr was part of a militia group that sent threatening letters featuring crosshairs similar to those in Zodiac communications. Although he was reportedly armed and had taught her cryptology, the lack of concrete evidence linking him directly to the murders left law enforcement disinterested in pursuing the case further.

2 Richard "Rick" Marshall

Marshall's Zodiac Link: The Theory

Richard "Rick" Marshall became a suspect in the Zodiac Killer case primarily due to his presence in Riverside, California, during the murder of Cheri Jo Bates in 1966. Several compelling connections were noted, including a typewritten letter sent to The Riverside Press that detailed Bates' murder with information not made public and signed with a "Z"-like symbol. Marshall, who later moved to San Francisco near the site of another Zodiac murder, was a fan of old movies, one of which, The Red Phantom, was referenced in a Zodiac letter.

Although many aspects of Marshall's life raised eyebrows, such as his ownership of a similar typewriter and his ambidexterity, evidence ultimately fell short.

Despite these connections, he denied any involvement in a 1989 interview, and investigators stated he wasn't a match. Although many aspects of Marshall's life raised eyebrows, such as his ownership of a similar typewriter and his ambidexterity, evidence ultimately fell short. Retired detective Ken Narlow remarked, "Marshall makes good reading but not a very good suspect in my estimation." Marshall acknowledged the similarities during an interview, saying, “My innocence notwithstanding, the details do fit.” He remained a suspect largely due to the fictional portrayals in Robert Graysmith’s book and the subsequent film adaptations.

1 Jack Tarrance

Tarrance's Zodiac Connection: The Claim

Jack Tarrance emerged as a suspect in the Zodiac Killer case after his stepson, Dennis Kaufman, alleged that Tarrance was the infamous serial killer. Kaufman claimed to have discovered blood-stained knives, a hood bearing the Zodiac symbol, and rolls of film depicting violent images at Tarrance's home. He also noted that Tarrance's physical appearance closely matched police sketches of the Zodiac Killer. Despite these accusations, a 2019 DNA comparison of Tarrance’s profile with that of the Zodiac Killer yielded inconclusive results, preventing any formal charges from being brought against him.

Kaufman further alleged that Tarrance made unsettling comments about violence, including, "If you knew who I was, you wouldn't like me very much," and boasted about his past, stating, "I've been drunk and in fights. I've stabbed so many people I've lost count." His half-brother, Charles, ed these claims, recalling that Tarrance mimicked shooting people while exclaiming, "Ha ha, Zodiac." While some skeptics suggest that Kaufman may have been misled by his family or motivated by financial gain, authorities have not pursued charges against Tarrance. As such, despite all the evidence exposed in This Is The Zodiac Speaking, the case remains a mystery.