Zodiac Killer and Black Dahlia Suspect Theories
Investigator Alex Baber claimed on July 6, 2026, to have cracked a Zodiac cipher using AI, identifying Marvin Margolis (alias Marvin Merrill) as a prime suspect in both the Zodiac Killer and Black Dahlia murder cases, leading law enforcement to approach Margolis's family for DNA samples. As of July 6, 2026, the LAPD is testing fingerprint evidence related to Margolis, marking the first time in decades specific physical evidence is being tested against a named individual in the Zodiac case. Baber announced his cipher solution in April 2026, detailing it in cryptanalytic and forensic papers. This development follows a December 2025 investigation and a May 2026 podcast proposing Margolis as a suspect for both cases, with other theories identifying suspects like Gary Francis Poste and Joseph Steven Holt.
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July 2026 — 2 developments
Investigator claims AI cracked Zodiac cipher, names new suspect linked to Black Dahlia
Investigator Alex Baber claims to have cracked a Zodiac cipher using AI, identifying Marvin Margolis (an alias for Marvin Merrill) as a prime suspect in both the Zodiac Killer and Black Dahlia murder cases. Law enforcement has reportedly approached Margolis's family for DNA samples in relation to the Black Dahlia case.
LAPD Confirms Testing Evidence on Marvin Margolis as Zodiac Killer Suspect
A podcast proposed in April/May 2026 that the Zodiac Killer and the Black Dahlia Avenger were the same person, Marvin Margolis. The LAPD confirmed in May 2026 that they were testing fingerprint evidence related to Margolis, marking a new development in the investigation.
June 2026 — 7 developments
LAPD Tests Physical Evidence in Zodiac Killer Case Linked to Marvin Margolis
The LAPD is testing physical evidence, including a fingerprint card, in connection with Marvin Margolis, a potential Zodiac Killer suspect identified through a deciphered cipher. This marks the first time in decades that specific physical evidence is being tested against a named individual in the Zodiac case.
Zodiac Killer Case: New Updates on Doer Files, Upcoming Books, and Cipher Attempts
New updates to the 'Doer Files' have been discussed, including Paul Doer's passport records. Upcoming books such as 'Zodiac Killer Solutions: The Findings of Dr Two Wolves' and 'Horrorscope' are also highlighted. Additionally, a new attempt to solve the Z13 cipher is detailed, amidst ongoing debates about the 340 cipher solution.
Investigator Claims New Cipher Solved, Names Marvin Merrill as Zodiac Killer Suspect
Cold case investigator Alex Baber announced in April 2026 that he cracked a 13-symbol Zodiac cipher, identifying Marvin Merrill as a previously uninvestigated suspect. The cipher solution was detailed in a series of cryptanalytic and forensic papers.
AI Reanalyzes Zodiac Killer's Final Letter, Suggesting New Meanings and Routines
A June 2026 video utilizing AI reanalyzed the Zodiac Killer's final letter, proposing that the number '37' may not refer to victims and suggesting the killer adhered to a Monday-to-Friday work schedule. This offers a fresh perspective on the killer's communications and potential routines.
Cold Case Team Claims Zodiac Killer Identified; New Suspect Proposed
The Case Breakers claim to have identified Gary Francis Poste as the Zodiac Killer, presenting evidence including photographic proof of scars matching a police sketch and anagrams from Zodiac letters. Separately, a December 2025 investigation proposed Marvin Margolis as a suspect for both the Zodiac killings and the Black Dahlia murder, citing evidence such as a sword and handwriting analysis.
New Book Names Lawrence Kane as Zodiac Killer Suspect, Proposes Z13 Cipher Solution
A new book published in May 2026 explores Lawrence Kane as a potential suspect in the Zodiac Killer case and proposes a solution to the Z13 cipher. This development follows recent news linking the Zodiac Killer to the Black Dahlia murder, with evidence reportedly under FBI review.
New Media Programs and Books Discuss Ongoing Zodiac Killer Case Investigations
New media discussions surrounding the Zodiac Killer case have emerged in June 2026, featuring a YouTube program titled 'The Zodiac Killer Hot Seat' and a book named 'Horrorscope.' These developments indicate continued public and investigative interest in the unsolved mystery.
May 2026 — 1 developments
New Suspect Joseph Holt Named in Donna Lass Murder; Dual-Authorship Theory Proposed for Zodiac Killings
Joseph Steven Holt has been identified as a suspect in the murder of Donna Lass, with potential links to other Zodiac crimes, according to geoprofiling research. A new 'Dual-Authorship Theory' also suggests Arthur Leigh Allen and Ross Sullivan were both involved in the Zodiac killings.
April 2026 — 1 developments
Investigator Alex Baber identifies Marvin Margolis as new Zodiac, Black Dahlia suspect
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
FBI Confirms Codebreakers Deciphered Zodiac Killer's 340 Cipher in 2020
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
Zodiackiller.com updates with classified email identifying new Zodiac suspect
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.
Zodiac Killer May Have Intentionally Created Cipher Errors; Donna Lass's Skull Identified
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.
Alex Baber claims to solve Zodiac and Black Dahlia cases in upcoming "IMPACT x Nightline" episode
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 Name Deceased Marine Marvin Merrill as New Zodiac, Black Dahlia Suspect
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.
Zodiac Killer may have used 'shifting 9' to scramble 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.
Eddie McNamera to release new book 'Zodia Actually' in March 2026
A new book titled 'Zodia Actually' by Eddie McNamera, promising to challenge existing theories, is set for release in March 2026.
Zodiac Killer's Halloween card analysis suggests self-identification as 'ME'
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 Crack Zodiac Killer's Z13 Cipher, Links Killer to 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.
Specialists Identify Zodiac Killer, Link Him to Another Murder; FBI Reviews New 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.
FBI reviews new Zodiac Killer theory linking case to Black Dahlia, identifying Marvin Margolis
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
Paul Avery's materials reveal new Zodiac suspect 'JOOST'
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
Vallejo Police Rule Out Genetic Profile in Zodiac Killer Case
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
Lake Harmony Author Proposes New Zodiac Killer Theory, Identifies Thoresen as Suspect
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 uses DNA technology to re-examine Zodiac Killer evidence
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
Mathematician Samuel Blake Deciphers Zodiac Killer 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
Netflix docuseries claims to identify Arthur Leigh Allen as 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
Case Breakers identify Air Force veteran Gary Francis Poste as Zodiac Killer
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
Investigators claim to identify Zodiac Killer, but law enforcement rejects claim
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
Amateur sleuths decipher Zodiac Killer cipher; investigators name Gary Francis Poste as 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
Zodiac Killer Claims 37 Victims in Last Confirmed Letter to 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
Zodiac Killer mailed 340-character cryptogram to 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
Zodiac Killer murders taxi driver Paul Stine, sends bloody shirt piece to San Francisco Chronicle
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
Killer attacks Bryan Hartnell and Cecelia Shepard at Lake Berryessa, Shepard dies
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
Zodiac Killer Sends Taunting Letters to Bay Area Newspapers, Claims Responsibility for 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 Shot at Blue Rock Springs Park; Ferrin Dies
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
Zodiac Killer murders Betty Lou Jensen and David Arthur Faraday in Benicia, California
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.