Zodiac Killer Investigations
Independent investigator Alex Baber claimed on April 2, 2026, to have identified Marvin Margolis as a new suspect in the Zodiac Killer case, also linking him to the Black Dahlia murder, with his theory (Z13) reportedly under review by the FBI and California police. As of April 2, 2026, new theories and potential suspects continue to emerge in the Zodiac Killer investigation, which remains unsolved. Cold case investigators previously named Marvin Merrill as a suspect on January 16, 2026, after decoding a 1970 Zodiac cipher, while a psychiatric nurse's classified email, updated on Zodiackiller.com on January 24, 2026, detailed a patient who committed suicide in 1977 as a potential suspect. The "340 cipher" was deciphered in December 2020 by international codebreakers, but it did not reveal the killer's identity.
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April 2026 — 1 developments
Independent investigator Alex Baber claims to have identified Marvin Margolis as a new suspect in the Zodiac Killer case, also linking him to the Black Dahlia murder.
Independent investigator Alex Baber claims to have identified Marvin Margolis as a new suspect in the Zodiac Killer case, also linking him to the Black Dahlia murder. Baber's evidence includes a sword, Margolis's proximity to the killings, and an interpretation of a 1992 sketch as a deathbed confession. This theory, referred to as Z13, is reportedly under review by the FBI and California police.
March 2026 — 1 developments
A new book, "Zodiac: The Final Cipher," released in April 2025, claims to present previously undisclosed evidence regarding the Zodiac Killer's identity.
A new book, "Zodiac: The Final Cipher," released in April 2025, claims to present previously undisclosed evidence regarding the Zodiac Killer's identity. As of June 2025, advances in DNA technology and genetic genealogy are being re-examined for potential leads. In December 2020, the FBI confirmed that a team of international codebreakers successfully deciphered the "340 cipher," which contained a message from the killer but did not reveal his identity.
January 2026 — 7 developments
The Zodiackiller.
The Zodiackiller.com website updated on January 24, 2026, featuring a previously classified email from a psychiatric nurse who believed a patient, who committed suicide in 1977, was the Zodiac Killer. This new information provides details on a potential suspect and a specific lead.
A new analysis explores how the Zodiac Killer may have intentionally created errors in the 340 cipher.
A new analysis explores how the Zodiac Killer may have intentionally created errors in the 340 cipher. Additionally, the skull of Donna Lass, a woman last seen in 1970 and theorized to be a Zodiac victim, was identified in a 50-year-old cold case.
An upcoming "IMPACT x Nightline" episode, titled "Kill Code: Black Dahlia & Zodiac — Two Cases, One Killer?
An upcoming "IMPACT x Nightline" episode, titled "Kill Code: Black Dahlia & Zodiac — Two Cases, One Killer?", will explore amateur sleuth Alex Baber's claim that he has solved both the Zodiac and Black Dahlia cases. The episode is scheduled to stream on January 22 on Disney+ and Hulu.
Cold case investigators have recently named Marvin Merrill, a former US Marine who died in 1993, as …
Cold case investigators have recently named Marvin Merrill, a former US Marine who died in 1993, as a new suspect in the Zodiac and Black Dahlia murders after decoding a 1970 Zodiac cipher. Merrill's family expressed deep skepticism, describing him as a pathological liar and con artist.
New analysis suggests the Zodiac Killer may have used a 'shifting 9' technique to scramble the 340 cipher.
New analysis suggests the Zodiac Killer may have used a 'shifting 9' technique to scramble the 340 cipher. Additionally, research into the Z38 code implies its sender possessed intrinsic knowledge of the 340 cipher's mechanics.
A new book titled 'Zodia Actually' by Eddie McNamera, promising to challenge existing theories, is set for release in March 2026.
A new book titled 'Zodia Actually' by Eddie McNamera, promising to challenge existing theories, is set for release in March 2026.
A new analysis of the Zodiac Killer's Halloween card suggests the killer might have identified himself as 'ME' through the words 'PEEK-A-BOO' and 'DOOMED.
A new analysis of the Zodiac Killer's Halloween card suggests the killer might have identified himself as 'ME' through the words 'PEEK-A-BOO' and 'DOOMED.' This interpretation delves into the killer's potential self-identification through the card's imagery.
December 2025 — 3 developments
Amateur sleuth Alex Baber claims to have cracked the Zodiac Killer's 13-symbol cipher (Z13) and theorizes that the Zodiac Killer is also responsible for the Black Dahlia murder.
Amateur sleuth Alex Baber claims to have cracked the Zodiac Killer's 13-symbol cipher (Z13) and theorizes that the Zodiac Killer is also responsible for the Black Dahlia murder. This new investigation suggests a single individual committed both infamous cold cases.
A team of specialists claims to have identified the Zodiac Killer and linked him to another murder, with the FBI reportedly reviewing new suspect information.
A team of specialists claims to have identified the Zodiac Killer and linked him to another murder, with the FBI reportedly reviewing new suspect information. Additionally, amateur codebreakers have deciphered a previously unsolved cipher from the Zodiac Killer nearly 50 years after his crimes.
The FBI is reportedly reviewing a new investigation that claims to have solved the Zodiac Killer cas…
The FBI is reportedly reviewing a new investigation that claims to have solved the Zodiac Killer case by linking it to the Black Dahlia murder and identifying Marvin Margolis as a suspect. This marks an official review of the new theory and suspect.
October 2025 — 1 developments
A previously unknown suspect named 'JOOST' has been revealed from the private materials of former Sa…
A previously unknown suspect named 'JOOST' has been revealed from the private materials of former San Francisco Chronicle reporter Paul Avery, a name not previously seen in amateur Zodiac investigations.
September 2025 — 1 developments
The Vallejo Police Department announced that a previously obtained genetic profile, which was being …
The Vallejo Police Department announced that a previously obtained genetic profile, which was being investigated in connection with the Zodiac Killer case, belonged to an individual who has now been definitively ruled out as the killer.
August 2025 — 1 developments
A Lake Harmony author proposes a new theory identifying a man named Thoresen as the Zodiac Killer, c…
A Lake Harmony author proposes a new theory identifying a man named Thoresen as the Zodiac Killer, claiming he committed at least 87 murders across 10 states and was never investigated due to FBI embarrassment.
July 2025 — 1 developments
Law enforcement and experts are focusing on utilizing modern DNA technology, including genetic genea…
Law enforcement and experts are focusing on utilizing modern DNA technology, including genetic genealogy, to re-examine evidence from the Zodiac Killer's letters and crime scenes in hopes of identifying the killer. This ongoing effort represents a distinct investigative approach.
May 2025 — 1 developments
A mathematician named Samuel Blake has reportedly deciphered the Zodiac Killer's ciphers using advanced algorithms.
A mathematician named Samuel Blake has reportedly deciphered the Zodiac Killer's ciphers using advanced algorithms. The deciphered messages are said to contain significant hidden information and have stunned investigators.
November 2024 — 1 developments
A new Netflix docuseries, "This Is the Zodiac Speaking," released in late 2024, claims to identify Arthur Leigh Allen as the Zodiac Killer.
A new Netflix docuseries, "This Is the Zodiac Speaking," released in late 2024, claims to identify Arthur Leigh Allen as the Zodiac Killer. The series features new information, including alleged confessions to the Seawater family, re-examining Allen as a prime suspect.
May 2023 — 1 developments
A cold case team, The Case Breakers, identified Air Force veteran Gary Francis Poste as the Zodiac K…
A cold case team, The Case Breakers, identified Air Force veteran Gary Francis Poste as the Zodiac Killer, claiming an FBI official confirmed Poste was listed as a suspect in FBI computers since 2016 and that a partial DNA sample exists.
October 2021 — 1 developments
A group of investigators claimed to have identified Gary Francis Poste as the Zodiac Killer, presenting evidence including witness claims and scars.
A group of investigators claimed to have identified Gary Francis Poste as the Zodiac Killer, presenting evidence including witness claims and scars. However, law enforcement officials, including the FBI, rejected the claim, stating the investigation remains open and unsolved.
December 2020 — 1 developments
A team of amateur sleuths deciphered a Zodiac Killer cipher sent in 1969, revealing messages from the killer.
A team of amateur sleuths deciphered a Zodiac Killer cipher sent in 1969, revealing messages from the killer. In 2021, independent cold-case investigators claimed to have identified Gary Francis Poste, an Air Force veteran who died in 2018, as the Zodiac Killer, citing evidence such as shoe size matches and facial features, and alleging Poste confessed to six people.
January 1974 — 1 developments
The last confirmed letter from the Zodiac Killer was received by the San Francisco Chronicle.
The last confirmed letter from the Zodiac Killer was received by the San Francisco Chronicle. In this letter, the Zodiac claimed to have killed 37 people.
November 1969 — 1 developments
The Zodiac mailed a card with a 340-character cryptogram (Z340) to the San Francisco Chronicle.
The Zodiac mailed a card with a 340-character cryptogram (Z340) to the San Francisco Chronicle. This cipher remained unsolved for 51 years.
October 1969 — 1 developments
Paul Stine, a taxi driver, was shot and killed in San Francisco.
Paul Stine, a taxi driver, was shot and killed in San Francisco. This was the last confirmed murder by the Zodiac. The killer sent a bloody piece of Stine's shirt to the San Francisco Chronicle.
September 1969 — 1 developments
Bryan Hartnell and Cecelia Shepard were attacked at Lake Berryessa in Napa County.
Bryan Hartnell and Cecelia Shepard were attacked at Lake Berryessa in Napa County. Shepard died from her stab wounds two days later, while Hartnell survived. The killer wore a hood and left a message on Hartnell's car door.
August 1969 — 1 developments
The Zodiac Killer sent the first of several taunting letters to Bay Area newspapers, taking credit for the Lake Herman Road and Blue Rock Springs attacks.
The Zodiac Killer sent the first of several taunting letters to Bay Area newspapers, taking credit for the Lake Herman Road and Blue Rock Springs attacks. These letters included cryptograms, with the first (Z408) being solved shortly after.
July 1969 — 1 developments
Michael Mageau and Darlene Ferrin were shot at Blue Rock Springs Park in Vallejo, California.
Michael Mageau and Darlene Ferrin were shot at Blue Rock Springs Park in Vallejo, California. Ferrin died, but Mageau survived and provided a description of the attacker.
December 1968 — 1 developments
The first confirmed murders attributed to the Zodiac Killer occurred when high school students Betty…
The first confirmed murders attributed to the Zodiac Killer occurred when high school students Betty Lou Jensen and David Arthur Faraday were shot and killed on Lake Herman Road in Benicia, California.