For more than 50 years, the Zodiac Killer has remained one of America’s most infamous unsolved mysteries. The unknown attacker was linked to at least five murders in Northern California between 1968 and 1969, taunting police with cryptic letters, coded messages, and a signature symbol that became synonymous with fear. Now, decades later, two very different names have re-emerged in the search for the killer’s identity: Gary Francis Poste and Richard Hoffman. The case began on December 20, 1968, near Lake Herman Road in Northern California.
Two teenagers—17-year-old Betty Lou Jensen and 16-year-old David Faraday—were shot and killed while on a date. There was no apparent motive, no robbery, and no clear connection between the victims and their attacker. At the time, police had no idea this was the beginning of a much larger investigation. Months later, on July 4, 1969, another attack occurred at Blue Rock Springs Park in Vallejo.
Darlene Ferrin was killed, and Michael Mageau was shot multiple times but survived. Mageau’s survival proved crucial, as he was able to describe the attacker as a heavyset white male with a large face and short hair. Shortly after the attack, a man called the Vallejo Police Department from a payphone, calmly reporting the shooting and claiming responsibility for the earlier murders. On August 1, 1969, letters were sent to three Bay Area newspapers.
The writer threatened more killings unless his message was published and included a cipher made of hundreds of symbols, claiming it would reveal his identity. A school teacher and his wife eventually solved the code, revealing disturbing content about the killer’s motives. Around this time, the attacker began using the name “Zodiac” and a symbol resembling a circle with a cross through it. The Zodiac struck again on September 27, 1969, at Lake Berryessa.
Two college students, Bryan Hartnell and Cecilia Shepard, were approached by a man wearing a black hood with the Zodiac symbol. He claimed to be an escaped prisoner, tied them up, and stabbed them repeatedly. Shepard later died, but Hartnell survived. The killer then wrote details of his earlier attacks on their car door and added his symbol.
Only two weeks later, on October 11, 1969, San Francisco taxi driver Paul Stine was shot and killed by a passenger. Several young witnesses saw the killer leave the cab, and he took a piece of Stine’s bloodied shirt. Officers nearby stopped and spoke with a man who may have been the killer, but a mistaken radio description—directing them to look for a Black suspect—allowed him to walk away. Days later, a newspaper received a letter containing Stine’s shirt fragment, signed with the Zodiac name.
Over the following decades, investigators examined thousands of suspects, letters, fingerprints, palm prints, handwriting samples, and witness accounts. Despite the volume of evidence, no one was ever officially identified as the Zodiac Killer. One of the biggest problems was an overwhelming amount of information that no single investigator could fully process. A major development came in December 2020, when three code-breakers deciphered the so-called “340 cipher,” which had remained unsolved for more than 50 years.
The message did not reveal the killer’s name, but it demonstrated the killer’s effort to conceal his identity and his enjoyment of the investigation as a game. Two other codes, known as Z13 and Z32, remain unsolved, with the Z32 linked to a map and directions involving Mount Diablo. In 2024, an artificial intelligence system was reportedly used to examine the entire collection of Zodiac-related information. Instead of focusing on one suspect at a time, the system compared names, dates, locations, handwriting habits, crime details, and other records to find hidden patterns.
According to claims surrounding the analysis, one name stood out: Gary Francis Poste. Poste was not a new name to investigators. He had reportedly been considered years earlier but was dismissed, partly because he did not fit the image investigators had built of the killer. Poste was described as a house painter, a former military man, and someone with experience using firearms.
The alleged AI analysis reportedly found multiple connections when his records were compared with the known facts of the case. Private investigators known as The Case Breakers later claimed Poste was the Zodiac Killer. Their theory drew on several details, including deep scars on Poste’s forehead from a 1959 car accident. They compared photographs of Poste with police sketches of the Zodiac and said the scars appeared in the same places with similar shapes.
Footprints found near the Lake Berryessa attack were reportedly military-style boots in size 10. 5, and Poste reportedly wore the same size during his Air Force service. Poste’s military training also attracted attention. He reportedly worked with radar and had experience with maps, numbers, calculations, communication, and patterns.
Investigators believed this could explain the Zodiac’s use of codes and symbols. The 1959 crash left Poste with severe facial injuries and required multiple operations. People close to him reportedly noticed changes in his behavior after the accident, describing him as colder, moodier, and sometimes violent. More disturbing claims came from people who said they knew Poste personally.
Some former associates described a secretive group of young men who followed him, with allegations that he taught them how to use guns, kill animals, and make explosives. One former member allegedly claimed Poste ordered the killing of another man. These claims remained allegations and were never officially proven. The Case Breakers also alleged that several people heard Poste admit he was the Zodiac before his death in 2018.
They claimed at least six people heard such statements and that three of those alleged confessions were written down in sworn statements. Alleged confessions, however, require careful verification, and no official confirmation has been made. Poste’s personal life also became part of the theory. Neighbors reportedly described his marriage as unusual, and his wife was said to have privately suspected he was hiding something dangerous but was too afraid to go to police.
A woman who lived near Poste as a child claimed he often took her into the woods to shoot guns and said the experience frightened her. These accounts remain unverified. While the Poste theory gained attention, a second suspect emerged from a very different source: family memory. Jay Foy, a former federal police officer and Marine Corps veteran, said he discovered his own grandfather might have been the Zodiac Killer.
His grandfather was Richard Hoffman, a former Vallejo police officer and detective who later worked as a law enforcement consultant on the 2007 film about the Zodiac case. Foy said he began researching his grandfather after wondering why he was the only person in his family to become a police officer. An online search revealed existing discussions connecting Hoffman to the Zodiac case. Foy said he spent about 13 hours without sleep going through websites, Reddit posts, and case material, becoming convinced his grandfather could have been the killer.
Foy pointed to similarities between old photographs of Hoffman and witness descriptions of the Zodiac—both described as heavyset men wearing glasses. He also noted Hoffman’s police background, arguing that an officer would understand how investigations worked, how evidence was processed, and how to avoid leaving fingerprints. Foy described his grandfather as strict, controlling, and strong-willed, with an interest in German history and a belief that he was superior to women. Another detail involved holidays.
Foy remembered his grandfather loved Halloween, Christmas, and Easter, which caught his attention because some Zodiac messages and activities were connected to special dates. His most significant claim, however, involved writing. Foy said he compared Hoffman’s police reports with Zodiac letters and believed both writers made the same unusual spelling mistakes. Foy also noted that Hoffman reportedly struggled with spelling and disliked crossword puzzles but enjoyed mathematics and solving equations.
This could matter, Foy argued, because the Zodiac’s ciphers required comfort with numbers and patterns. Woodworking experience was another potential link, since investigators struggled to find usable fingerprints and discussed the possibility that the killer used wood adhesive or similar materials to conceal his prints. Foy’s theory also reached back to the 1966 murder of Cheri Jo Bates, which some have suggested may have been an early Zodiac attack. Bates was killed before the four main Zodiac murders, and the connection has never been officially proven.
Foy noted that Hoffman had served in the Navy and was stationed in Nebraska, while Bates was also from Nebraska, and a military-style footprint was reportedly found at the crime scene. A poem found beneath a desk in the library where Bates was killed reportedly carried the initials “RH,” which could stand for Richard Hoffman. Both theories—Poste and Hoffman—remain unproven. The Zodiac Killer’s identity has never been officially confirmed, and neither the alleged AI findings, private investigator claims, nor family memories have resulted in a formal legal determination.
Letters still surface from time to time, and the unsolved ciphers continue to attract amateur code-breakers and professional investigators alike. After 55 years, the case remains open, and the question of who was truly behind the Zodiac symbol has not been answered with certainty.
