TLDR
Cold case consultant Alex Baber, who argues the Zodiac Killer and the Black Dahlia murderer were the same man, will unveil new details at the Hamptons true crime festival, Hamptons Whodunit.
One Theory, Two Infamous Crimes
In East Hampton, inside a quiet library more used to beach reads than bloodstained history, one of true crime’s most divisive theories is about to be argued in public. The man behind it, investigative consultant Alex Baber, insists two of the most infamous unsolved cases in America are not separate nightmares, but chapters in the same story.
Baber, director of Cold Case Consultants of America, electrified the true crime world when his work was first reported by the Daily Mail. After a years-long investigation, he concluded that the Zodiac Killer, who terrorized Northern California in the late 1960s, and the still-unknown Black Dahlia murderer, who struck Los Angeles in 1947, were the same person, Second World War veteran Marvin Margolis.
Now that theory moves from the page to the stage. At the Hamptons Whodunit festival in East Hampton, New York, Baber will headline a marquee panel titled “Behind the Headlines: One Theory That Could Change True Crime History.” Joining him are Daily Mail Senior Correspondent Kayla Brantley and The Crime Desk US Editor Rachel Sharp, the journalist who first brought Baber’s work to a global audience.
It is a high-profile platform for a controversial idea. Between 1968 and 1969, the Zodiac Killer claimed responsibility for a string of attacks in Northern California, taunting police and newspapers with ciphers and letters. Two decades earlier, aspiring actress Elizabeth Short, later immortalized as the Black Dahlia, was found murdered and gruesomely posed in Los Angeles. For generations, they have lived in separate corners of American folklore.
According to Baber, the cases intersect in code. He says he has cracked the Zodiac’s notorious Z32 cipher and uncovered a message that, in his view, points straight back to the Black Dahlia killing and to Margolis. Law enforcement has not publicly endorsed his conclusion, which leaves his findings in a tense space between breakthrough and disputed theory.
In December 2025, the Daily Mail laid out Baber’s work in detail, describing an investigation spanning military records, crime-scene evidence, and decades of competing suspects. The Hamptons panel promises to go even further, with Baber expected to share new developments and hint at additional cold cases on his desk.
A Claim Under the Spotlight
Baber has framed the event as more than a spotlight moment. He told the Daily Mail, “I am honored to be invited to participate in the upcoming Hamptons Whodunit panel. It represents a valuable opportunity to engage in substantive discussion alongside respected voices in the field, with a shared focus on investigative integrity and the thoughtful examination of complex cases.” He added that he appreciates the Daily Mail’s role in “supporting and amplifying this event” and its commitment to “meaningful, in-depth stories” that fuel informed public debate.
Hamptons Whodunit, which blends real-world crime experts with bestselling mystery and thriller authors, is positioning Baber’s appearance as a centerpiece of its programming. CEO and co-founder Carrie Doyle said, “We are excited to collaborate with The Daily Mail to showcase the incredible true crime and forensic experts as well as the bestselling mystery and thriller authors that are featured at Hamptons Whodunit.” She described the festival as “a unique interactive weekend where our attendees can hear all about crime from those solving real cases, as well as from those who are creating fictional mysteries in their books.”
Doyle added that the partnership with the Daily Mail allows organizers to bring “riveting stories of the quest for justice not just to our local audience, but to the masses.” For Baber, that mass audience now becomes an informal jury. If his theory about Zodiac, the Black Dahlia, and Marvin Margolis withstands scrutiny in that room, it will not only reshape how two infamous crimes are remembered but also define his legacy in the ever-expanding universe of true crime.
Do you see Baber’s theory as a long-overdue breakthrough, or do Zodiac and the Black Dahlia still feel like separate legends to you? Share where you stand, and which unanswered question you most want addressed when the lights go up in East Hampton.
