Groundbreaking developments have emerged in the investigation of whether a single individual might be linked to both the Black Dahlia murder and the Zodiac killings—two of the most notorious cold cases in U.S. history.

Alex Baber, the director of Cold Case Consultants of America, shook the true crime community when he exclusively disclosed to the Daily Mail last December his theory that both crimes were perpetrated by the same man: Marvin Margolis, a deceased World War II veteran and father of four.

Since then, the investigation has taken a significant and unexpected turn.

Speaking at the Daily Mail-sponsored Hamptons Whodunit event in East Hampton, New York, on Friday, Baber revealed for the first time that detectives are in the process of obtaining a DNA sample related to the Black Dahlia case. This marks a step that had not been pursued in the nearly 80 years since Elizabeth Short’s brutal murder and display on a Los Angeles street.

Baber joined a headline panel with Daily Mail Senior Correspondent Kayla Brantley and The Crime Desk US Editor Rachel Sharp, who originally reported the groundbreaking story identifying Margolis.

“I can only reveal so much,” Baber stated. “I just got off the phone with them this week. Detectives have sought a DNA sample for the Black Dahlia case. That’s a first. Although the family declined, we’re exploring new forensic avenues as we speak.”

He added: ‘I promise you, the wheels are turning, and we’re coming close to putting an end to this mystery.’

Alex Baber – the investigative consultant who stunned the true crime world by concluding the Zodiac Killer and the Black Dahlia murderer were the same man – is taking that theory inside one of the country’s most talked-about crime events 

Elizabeth Short – later known as the Black Dahlia – was found brutally murdered in Los Angeles in 1947, her body severed in half and grotesquely posed, a chilling detail that horrified the nation 

Baber said the investigation has been bolstered by a critical shift within Margolis’s own family, revealing during the panel that some relatives are now cooperating with investigators.

He also disclosed another significant development: newly surfaced video footage showing Margolis alongside his close associate Bill Robinson years after Elizabeth Short’s murder – a direct contradiction of the version of events both men gave to investigators at the time.

According to grand jury records, Robinson – a former member of the Army’s Signal Intelligence Service, the military’s codebreaking unit – was part of Margolis’s inner circle during the period when Baber alleges he was involved with Short.

Both men had insisted they were no longer in contact by the time police began investigating her killing in 1947.

The footage, Baber said, places them together well after her death – raising fresh questions about what they told detectives and whether key elements of the original investigation were built on false premises.

It also underscores Robinson’s potential significance beyond the Dahlia case. As a wartime codebreaker trained in classical cryptographic techniques, Baber suggested, Robinson could have helped lay the groundwork for the cipher-based taunts that would later define the Zodiac killer’s reign of terror two decades later.

Between 1968 and 1969, the Zodiac killer terrorized Northern California, murdering at least five victims while claiming many more. He taunted police and the media with cryptic letters and ciphers – daring anyone to uncover his identity.

The Zodiac’s spree came 21 years after Short’s murder sent shockwaves through California.

Short – later dubbed the Black Dahlia in the press – was found brutally murdered in Los Angeles, her body severed in half and grotesquely posed, a chilling detail that horrified the nation.

Both cases stumped investigators, leading to decades of dead ends and failed theories.

Investigator Alex Baber spoke on a headline panel alongside The Crime Desk US Editor Rachel Sharp on Friday, sharing their investigation into Margolis

Then, in December 2025, the Daily Mail revealed Baber’s claim that he had finally solved both cases following an exhaustive, years-long investigation.

He says he has also cracked the Zodiac’s infamous Z32 cipher – uncovering a message he believes directly links the killer to the Black Dahlia murder.

Speaking during the panel on Friday, Baber said that solving the cases and unmasking Margolis were personal for him.

Shortly before landing on Margolis as a suspect, Baber spoke with Short’s last surviving sibling, who told him she had long given up hope of ever learning who killed her sister.

‘This is hard for me to talk about,’ he said, his voice cracking with emotion. ‘But she told me, “We gave up hope a long time ago that they would ever identify her murderer… my four sisters have died, and my mother passed in ’92, and I don’t think I’ll ever know.”

‘Before I hung up, I said: “Let me give you my word – I’ll find him for you.” And she died just as I identified him officially, so I missed her by a few months.

‘That was hard to swallow.’

Baber and Sharp’s presentation of the evidence against Margolis appeared to stun many inside East Hampton Library.

During a Q&A at the end of the panel, a former detective in the audience exclaimed, ‘You’re f**king amazing,’ to Baber.

Marvin Margolis in a high school yearbook photo (left) and a later photo obtained and enhanced by Baber. His solution to the Z13 cipher reveals the name Marvin Merrill, an alias used by Marvin Margolis, a man who was a prime suspect in the Black Dahlia murder 

Friday’s panel was held at the Daily Mail-sponsored Hamptons Whodunit event in East Hampton, New York. The panel was moderated by Daily Mail Senior Correspondent Kayla Brantley (center)

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Hamptons Whodunit CEO and co-founder Carrie Doyle spoke of her excitement about Baber and Sharp’s seminar earlier this week.

‘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 said.

‘Our festival is 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.

‘Hamptons Whodunit’s partnership with The Daily Mail allows us to bring riveting stories of the quest for justice not just to our local audience, but to the masses.’