The letter almost completes the sentence for you. “My name is,” the writer announces. Then ordinary handwriting gives way to thirteen symbols. Mailed to the San Francisco Chronicle on April 20, 1970, the page appears to offer the thing investigators and a frightened public wanted most: a way to put a name to Zodiac. More than half a century later, that unfinished introduction still draws people in. April 20 letter, reproduced in Tom Voigt’s archive
A new proposal says the symbols point to a man connected to the Black Dahlia investigation. Its supporters describe a specific cipher construction and publish summaries of their arguments. The question is whether their route to a name establishes what Zodiac intended—and whether it can identify the person behind the crimes. Those are separate hurdles.
Listen to Zodiac Killer: Why the New Cipher Claim Does Not Name Him Yet. The episode follows the letters, the genuine code-breaking breakthroughs and the proposed link to Elizabeth Short, testing each step between a reading and an identification.
He had offered his identity before
By the time those thirteen symbols arrived, the killer’s correspondence had already made the possibility of a hidden identity part of the public story. The FBI’s historical account describes a three-part coded message sent to newspapers in 1969. The message was decoded, but the name people hoped to find did not emerge. Meanwhile, local investigators sought the Bureau’s help with handwriting, fingerprints and cryptanalysis. A readable message and an identified murderer remained different outcomes. FBI’s archived case overview
That history changes how the April letter reads. The words above the cipher are a promise made by a man who threatened people through the newspapers. They give us a reason to investigate the marks. They give us no assurance that he wrote his legal name beneath them.
Even now, it is easy to let the sentence do some of the decoding. A name feels like the natural ending. An alias, a joke or a deliberate false trail would leave the same invitation on the page.
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Discover Darkness and LightThe breakthrough that really happened
In December 2020, a different Zodiac cipher finally yielded. David Oranchak, Sam Blake and Jarl Van Eycke solved the 340-character message that had resisted readers for 51 years.
Their work involved changing the order in which the symbols were read and recovering the letters they represented. Blake’s account describes the excitement of a promising first section—and the further work needed to make sense of the remaining sections. A few encouraging words were a beginning. They still had to account for the rest of the page. The team submitted its solution to the FBI, which confirmed it. Sam Blake’s first-person account
The recovered message did not identify Zodiac. It did, however, give other researchers a substantial body of text and a procedure to examine. In their technical paper, the solvers explain why the much shorter Z13 presents a different problem: under simple substitution assumptions, many plausible answers can fit. Additional complications can expand those possibilities. They describe the need for stronger confirming evidence. Oranchak, Blake and Van Eycke’s technical paper, section 8.2.1
That is the difficulty hidden inside the short line. Thirteen symbols look more manageable than 340. They also give a proposed answer far fewer opportunities to be proved wrong.
The name in the new claim
In an April 24, 2026 interview, investigator Alex Baber described a two-layer method involving a two-by-seven grid. He said it produced “Marvin Merrill,” which he linked to Marvin Margolis and to the investigation into Elizabeth Short’s 1947 murder. These are Baber’s assertions about the cipher and the historical connection; they do not establish the proposed suspect’s responsibility for a crime. Baber’s interview with Fox News
The supporters’ website describes four papers, including a proposed rearrangement of the symbols and keyword arguments involving Elizabeth and Cherijo. That makes the proposal more specific than simply placing a suspect’s name beneath the marks. Rearrangement is a legitimate cryptographic technique; the solved 340-character cipher used it too. Claimants’ research summaries
Our review could read those summaries, but the linked technical PDFs returned errors. We have not independently reproduced their calculations. The distinction matters: we can describe the method its supporters claim, while leaving its statistical conclusions unverified.
What would make the name convincing?
Imagine receiving the thirteen symbols without a suspect file beside them. Would the proposed rules lead you to the same name? How were the grid, reading direction and keywords selected? What happens when other names are tried under the same rules?
Those questions test whether the method discovers an answer or accommodates one. If a suspected connection to Elizabeth Short helped select a keyword, that keyword’s apparent success cannot automatically count as independent confirmation of the connection. This is a question about the reasoning, rather than a claim that we have reconstructed the researchers’ search history.
A record created by the sender that documented the exact procedure would change the discussion. So would independently authenticated evidence connecting a person to the letters or crimes. A proposed link to Short’s murder would also need evidence from that investigation. A name emerging from a cryptogram cannot carry both cases by itself.
Hear the steps between the symbols and the suspect
The appeal of the April letter survives every new theory. Its opening makes an answer seem close enough to read. The work begins when we ask how that answer was obtained.
In Zodiac Killer: Why the New Cipher Claim Does Not Name Him Yet, we follow the earlier solved messages before returning to the thirteen marks, the proposed alias and the Black Dahlia connection. Hearing that sequence makes the crucial transitions easier to catch: where the documents end, where interpretation begins, and what would have to be checked next. You can also listen on Spreaker.
For another disputed attempt to identify a killer, read Could a shawl identify Jack the Ripper?
Featured image: AI-generated editorial illustration of correspondence and a magnifying lens; not a historical photograph or a reproduction of Zodiac evidence.
