An independent cold case investigator says he spent nine months breaking one of the Zodiac Killer's most stubborn coded messages, and that the name hidden inside it points not to a new serial killer suspect, but to a man already linked to the 1947 murder of aspiring actress Elizabeth Short, the case known worldwide as the Black Dahlia.
Alex Baber, co-founder of Cold Case Consultants of America, told Fox News Digital that his decryption of the Zodiac's 13-character "Z13" cipher produced the name "Marvin Merrill", which he says was an alias for the late Marvin Margolis, a military veteran, convicted fraudster, and onetime person of interest in the Black Dahlia investigation.
If Baber is right, two of the most notorious unsolved cases in American criminal history share a perpetrator. That is a staggering claim. And it rests, so far, almost entirely on the work of one man and a set of circumstantial connections that no law enforcement agency has publicly endorsed.
The Zodiac Killer terrorized California in the 1960s and 1970s, taunting police and newspapers with cryptic letters. Authorities have confirmed five murders and two injuries, though the killer himself boasted of 37 victims. No suspect has ever been charged.
Over the decades, several names have circulated, convicted sex offender Arthur Leigh Allen, late American painter Gary Francis Poste, but none has stuck. The Z13 cipher, a 13-character coded message embedded in one of the Zodiac's letters, has resisted professional and amateur codebreakers for more than half a century.
Baber says he cracked it using a two-layer encryption method involving transposition and substitution arranged in a 2×7 grid, as first detailed in a VT report. He used AI software and his own cryptographic knowledge to generate 71 million possible 13-letter names, then narrowed the field through pattern analysis and his interpretation of the cipher's structure.
The result, he says, was a single name: Marvin Merrill.
Baber then searched Social Security records and claimed that "Marvin Merrill" was an alias used by Marvin Margolis. That trail, he argues, leads straight to the Black Dahlia.
Elizabeth Short's body was found in January 1947 in a vacant lot in Leimert Park, Los Angeles. The details of the crime remain among the grisliest in American murder history: her remains were cut in half at the waist, her mouth slashed from ear to ear, her body apparently drained of blood and washed. No blood was found at the scene. Despite one of the largest investigations in LAPD history, no one was ever charged.
Cold cases that linger for decades often break open years later on a single piece of evidence or a fresh lead, and Baber believes his cipher work is that break. He contends that the victim's first name, Elizabeth, was itself the key to solving the Z13, generating the numerical sequence used to rearrange the cipher text.
Margolis, Baber says, dated Short in the 1940s and was already a previous suspect in her murder. The New York Post reported that Margolis was a World War II Navy medic with experience handling severe battlefield injuries, a background Baber argues could explain the surgical precision of the Black Dahlia mutilation. Additional circumstantial links, the Post noted, include claims that Margolis lived with Short, that his son later showed Baber a Japanese bayonet, and that a late-life drawing titled "Elizabeth" appeared to reference both the Black Dahlia and the word "Zodiac."
Baber says he visited Margolis's surviving son, unnamed in all available reporting, and that the encounter was unlike any interview he had conducted before. He described the son's response to Fox News Digital:
"He immediately turned white, his hands started shaking and he reached across the table, when he grabbed my hand. First time I've ever had an interview where they've initiated physical contact with me, and at that point, he says, 'We're gonna be OK.'"
Baber said the son then brought out handwriting samples from his father, produced a sketch, and showed him a picture allegedly drawn by Margolis more than 40 years after Short's death. When Baber mentioned Elizabeth Short's name, the son reportedly replied: "Elizabeth? Well, let me show you something."
That kind of reaction makes for a compelling story. Whether it constitutes evidence is another matter entirely.
Baber made one claim in April at East Hampton Library that, if true, would mark a genuine milestone. He told Fox News Digital:
"Currently, for the first time in history, LAPD detectives approached the family of a suspect to obtain DNA. That's never happened for the Black Dahlia case... we got a pretty good feeling that we're sitting in the right seat."
But Baber also told the Daily Mail that the DNA request was ultimately rejected by the Margolis family. And no independent confirmation from the LAPD has surfaced to verify that detectives approached the family at all.
That gap matters. In high-profile cold cases, tips and leads often run into institutional friction, agencies that guard their turf, families that refuse cooperation, evidence that degrades over decades. Baber's frustration may be genuine. But a claim that police acted is not the same as police confirming they acted.
Baber has expressed confidence that progress is still being made. He said: "We have some new things going on on the forensic side of these cases as we speak. I promise you, the wheels are turning, and we're coming close to putting an end to this mystery."
Not everyone dismisses Baber's work. The New York Post reported that former NSA chief codebreaker Ed Giorgio reviewed Baber's methodology and said: "All of [Baber's] work checked out to me." That is not a trivial endorsement, Giorgio's credentials in signals intelligence and cryptanalysis carry weight.
Baber himself has acknowledged the obsessive nature of his pursuit. He told the LA Times, as quoted by the Post: "It's my autism. Once I start on something, I have to see it through. The deeper I go, the harder I push. My mind's wired differently."
Other experts and former investigators, the Post noted, remain skeptical. And skepticism is the appropriate default when an amateur researcher claims to have solved two of the most famous unsolved cases in American history simultaneously. Long-running mysteries, from kidnappings to suspicious deaths, attract theories the way open water attracts boats. Most sink.
The list of things Baber has not yet established is longer than the list of things he has. No law enforcement agency has publicly adopted his conclusion. No suspect has been charged in either the Zodiac Killer case or the Black Dahlia case. No independent body has verified that "Marvin Merrill" was an alias for Marvin Margolis, beyond Baber's own Social Security records search. The original Z13 cipher text and Baber's full decryption methodology have not been published in a peer-reviewed or independently auditable format.
The DNA angle, potentially the strongest avenue for confirmation or elimination, appears to have hit a wall with the family's refusal.
Discoveries in cold cases sometimes emerge from unexpected places and unconventional investigators. Baber may well be onto something. A former NSA codebreaker reviewed his work and found it sound. The son's reported reaction, if accurately described, is difficult to dismiss. And Baber's willingness to share his findings with law enforcement and outside experts suggests he is not simply chasing publicity.
But "may be onto something" is not the same as proof. Authorities have spent decades on both of these cases without gathering enough evidence to charge anyone. One researcher's cipher solution, however sophisticated, does not change that unless it leads to physical evidence, DNA confirmation, or an official finding.
The enduring grip of the Zodiac and Black Dahlia cases on the American imagination says something about what happens when the justice system fails to close the book. Victims' families wait. The public speculates. Amateurs fill the vacuum that professionals left open. Some of those amateurs are cranks. Some turn out to be right.
Alex Baber's theory is the most detailed and methodologically grounded attempt in years to connect these two cold cases. It deserves serious scrutiny, from cryptographers, from law enforcement, and from the public. What it does not yet deserve is the certainty that some headlines have given it.
In a country that still values due process, the distance between a promising lead and a solved case is measured in evidence, not enthusiasm.
