Enochian Biosciences co-founder Serhat Gumrukcu was working to build a name for himself in biotech. But earlier this year, he was arrested in a purported plot to kill an associate. WSJ’s Joseph Walker tells the story of Gumrukcu’s rise and what prosecutors allege happened. Further Reading:

-Biotech Wizard Left a Trail of Fraud – Prosecutors Allege it Ended in Murder 

This transcript was prepared by a transcription service. This version may not be in its final form and may be updated.

Speaker 1: On a winter night in 2018, a man walked up to Greg and Melissa Davis's house and knocked on their door.

Speaker 2: I think about around 9:00 at night, a guy shows up at their door and he use a vehicle out front that looks like a police vehicle. He is wearing a mask that says US Marshall. He is presents himself as a US Marshall and says that, "I have a warrant here for your arrest. I need you to come with me."

Speaker 1: That's our colleague, Joe Walker. And according to court documents, the man at the door was carrying a rifle and handcuffs. He said he was there to arrest Greg Davis on racketeering charges.

Speaker 2: And Greg Davis says, "Okay, I'm going to go get dressed." He goes upstairs, he tells his wife what's happened. Exactly what was said between them, isn't so clear, but he goes back downstairs and he leaves with this man, who says that he is with the US Marshall service.

Speaker 1: When Davis walked out of his house that night, it was the last time his family ever saw him.

Speaker 2: The next day. Some drivers by, notice a body on the side of a road in a snowbank, and they call the police. And it's Greg Davis, where he is handcuffed and has been shot and killed.

Speaker 1: Four years later, authorities arrested the man who they say directed the plot to kill Davis. A biotech executive named Serhat Gumrukcu, Gumrukcu had been a typical tech entrepreneur in LA. He had a multimillion dollar home in Hollywood, and a company traded on the Nasdaq. But now he's in jail charged with murder and awaiting trial, through his lawyer, Gumrukcu denies the charges.

Speaker 2: It's just intrinsically and obviously really interesting to have a biotech entrepreneur, and self-proclaimed scientist, and physician allegedly be wrapped up in hiring hitman to murder somebody.

Speaker 1: Welcome to The Journal. Our show about money, business, and power. I'm Kate Linebaugh. It's Tuesday, August 2nd. Coming up on the show, a biotech entrepreneur, a trail of fraud and a murder. Earlier this year, our colleague Joe Walker, who covers biotech, was sitting at his desk preparing for an afternoon interview. When something grabbed his attention.

Speaker 2: An email came across from the department of justice that said, two men indicted in a murder for hire conspiracy. And when I looked at the press release the first name there was Serhat Gumrukcu, and I immediately thought, "Wow, this can't possibly be the same guy." Can it? But it must be, because how many Serhat Gumrukcu's are there? And so I started trying to learn more. I called the US attorney's office that had put out the release, and soon the stock started plummeting, and it became clear that it was the same person.

Speaker 1: Joe started to dig into the story. He poured over federal state and local records. He interviewed dozens of people who worked with Gumrukcu, and there was one description that stuck with him.

Speaker 2: Gentle is the word people use a lot, sort of soft spoken. He's 39, he comes from Turkey, he speaks very fluent English, as well as several other languages, apparently.

Speaker 1: Here he is on a podcast last year.

Speaker 3: There's no such thing as failure. And if you know, there's no such thing as failure, then you don't need to have confidence. It's not confidence, it's just this state of contentment-

Speaker 2: He is someone who has been able to make a lot of friends, a lot of business contacts. And a very short period of time, something of a charmer...

Speaker 1: When he was growing up in Turkey, one of his hobbies was performing magic. In a video from 2002, Gumrukcu is on stage.

Speaker 4: Now, the next guy is a medical student. Dr. (inaudible).

Speaker 2: So Serhat is in the video, and he is playing with these canes, and they look like they're levitating. And he's walking around the stage and doing some magic ring stuff as well. And just a pretty straightforward magic show type of performance.

Speaker 1: Gumrukcu eventually left Turkey, and in 2013, he moved to the US. He got married, and bought a million dollar home in Hollywood the following year. And he became interested in developing new drugs, and making connections with influencers in healthcare. And he caught people's attention like Mark Dybul, a Georgetown professor who became CEO of Gumrukcu's biotech business. Here's Dybul last year.

Speaker 5: Dr. Serhat Gumrukcu is a genius. I've been fortunate to be meet the top scientists in the world, including Nobel Laureate, he's up there with them. He has a remarkable genius mind, that sees across different scientific disciplines to come up with innovative solutions. The kind, when you see them, you say, "Aha, why didn't we think of that 20 years ago."

Speaker 1: Gumrukcu was known in the science community for trying out unconventional ideas, like treating patients with leeches. Here he is.

Speaker 3: It's a treatment modality that's been around for 3,000, 4,000 years, in Egypt, India, China. And then during the medieval times they got a bad rap, because they tried using leeches everything and for everything, and no medicine will be good for everything. So you had to-

Speaker 1: He was also persuasive in treating patients desperate for help.

Speaker 2: So in Pennsylvania, in 2016, he was sued by a family, where they said that he had come to Pennsylvania to treat the mother and the son, young man with cancer, gave him several treatments. And then the young man died from the cancer, and so in the lawsuit, this family alleges that the money that they gave him for more cancer treatments, which he did not deliver after the guy died. Serhat did not pay them back for that money.

Speaker 1: Gumrukcu hasn't commented on that case. He later paid a judgment set by the court, when asked about the case this year, his lawyer said that he isn't licensed to practice medicine in the US, and that he's never treated patients. Gumrukcu continued to have big ambitions, one idea was trying to cure HIV, using a one time cell transplant aimed at stopping the virus's attack. The idea had been tried before, but failed, and Gumrukcu claimed to have come up with a way to make it work. In April 2017, he registered a company, Gumrukcu Health LLC, and he quickly attracted interest, within weeks he was consulting with a European businessman, René Sindlev.

Speaker 2: René is an investor in an existing biotech company based in Denmark, and him and Serhat somehow connect. And within the next year or so in 2017, there is a deal to merge the Danish biotech firm with Serhat's company. That he had founded with his husband and another fellow that they were friends with, who had a background as an internet entrepreneur.

Speaker 1: As Gumrukcu's biotech ambitions were coming together. He was also working on other ventures, everything from flipping real estate to trading oil. And in one deal, he worked with a former commodities trader Greg Davis, the man who was founded in Vermont.

Speaker 2: Serhat and his brother Murat allegedly had a deal, where they were going to essentially put up a bunch of money. So that Greg Davis in Vermont could basically pull off the sale of some fuel, some oil, fuel in which he was going to make a profit.

Speaker 1: But that oil deal went very wrong. That's coming up. Serhat Gumrukcu and Greg Davis were moving forward with their oil deal. As part of it, prosecutor say Gumrukcu needed to pay Davis $600,000, but the checks Gumrukcu wrote were bad, they were from overdrawn accounts. So Davis didn't get the money, and prosecutors say, "He told his wife, he was being defrauded."

Speaker 2: Greg Davis is saying, Serhat and Murat, they need to make good on their contractual obligations, they haven't done so. I received banking documentation, and then when I called the bank that it supposedly came from in the middle east to verify it, they told me they had no idea what I was talking about.

Speaker 1: While Davis was trying to get his money, Gumrukcu was working on a big business deal. He was negotiating a major investment and a merger that would create his Nasdaq traded company Enochian Biosciences. Prosecutors say, Gumrukcu didn't want Davis to interfere with that deal going through, and that Davis was threatening to go to the authorities. But based on Joe's reporting, Davis didn't go to the authorities. And five days before Gumrukcu's big deal went through, law enforcement officers found Davis's body. The next day, according to prosecutors, they interviewed his wife.

Speaker 2: Prosecutors say that, she explained that he was involved with a business deal with the Gumrukcu brother, Serhat and Murat. And he thought that he was being defrauded, also what happens is that... Because somebody who had been allegedly posing as being with the US Marshall service had taken Greg Davis away, and was the last person to be seen with him before he was found murdered. The FBI is also involved right from the get go.

Speaker 1: So investigators started trying to piece together, who killed Davis and why. And from their interview with his wife, they were looking into Gumrukcu.

Speaker 2: And using shoe leather investigative techniques, like trying to find license plate numbers, and who bought the vehicle that the suspect was in, at the time that Greg Davis was murdered. They eventually track down who they think is the hitman, the trigger man.

Speaker 1: And in April, investigators arrested the man they allege, posed as a US Marshall and killed Davis.

Speaker 2: And they also find who they think is the connection between the trigger man and the Gumrukcu's. Prosecutors say that they interview a guy in Nevada named Aaron Lee Ethridge, who they believe is connected to the hitman. And the first interview, Ethridge doesn't say much. What they say is that he denies involvement, he denies knowing anything about it. And then not long after that comes back of his own volition voluntarily and says, "I did it, I'm going to tell you everything I know, I know the jig is up." And so what Ethridge tells the FBI is that, essentially he was contacted by a guy in Nevada who is a close family friend of Serhat's, and they arranged to have Gregory Davis killed.

Speaker 1: This is what prosecutors laid out in court documents. And it's how they allege Gumrukcu was connected to Davis's murder.

Speaker 2: Then May, Serhat is at LAX airport in Los Angeles, about to fly to New York. And he is arrested there by the federal agents, as is his family friend in Nevada at about the same time. Prosecutors say that Mr. Gumrukcu and his alleged co-conspirators, likely thought that they had gotten away with it.

Speaker 1: And what do prosecutors alleged was Gumrukcu's motivation?

Speaker 2: Prosecutors alleged that Gumrukcu's motivation to kill Davis, was to keep him from sounding the alarm on this alleged fraud, that he thought he was the victim of, and derailing the Enochian Biosciences deal.

Speaker 1: And what happens now?

Speaker 2: Well, we don't know what happens next exactly. But this is a federal case and the wheels of justice will probably grind fairly slowly. Mr. Gumrukcu would then be transferred to Vermont, where these charges were filed against him, and he will eventually go to trial.

Speaker 1: A federal grand jury indicted him on murder conspiracy charges, an offense that's punishable by death. Gumrukcu has denied the charges through his lawyer.

Speaker 2: The whole thing. I mean, it's like sort of a fascinating guy, right? I mean, he is fairly young guy, he's spending spoons at dinner to impress people. And he is insinuating himself into the social circles of quite powerful and wealthy people. And he's doing all different business deals to make money, and leaves behind this trail of alleged fraud. But there was no real sign that he was going to be derailed at all, if anything, his star was only ascending. And so then to have this murder for hire allegation is very shocking to the public, but also to people who knew him intimately.

Speaker 1: That's all for today, Tuesday, August 2nd. The Journal is a co-production of Gimlet and The Wall Street Journal. If you like our show, follow us on Spotify or wherever you get your podcast. We're out every weekday afternoon. Thanks for listening. See you tomorrow.

Kate Linebaugh is the co-host of The Journal. She has worked at The Wall Street Journal for 15 years, most recently as the deputy U.S. news coverage chief. Kate started at the Journal in Hong Kong, stopping in Detroit and coming to New York in 2011. As a reporter, she covered everything from post-9/11 Afghanistan to the 2004 Asian tsunami, from Toyota's sudden acceleration recall to General Electric. She holds a bachelor degree from the University of Michigan in Ann Arbor and went back to campus in 2007 for a Knight-Wallace fellowship.

Ryan Knutson is the co-host of The Journal. Previously, he spent more than four years in the newsroom covering the wireless industry, and was responsible for a string of scoops including Verizon's $130 billion buyout of Vodafone's stake in their joint venture, Sprint and T-Mobile's never ending courtship and a hack of the 911 emergency system that spread virally on Twitter. He was also a regular author of A-heds, including one about millennials discovering TV antennas. Previously, he reported for ProPublica, PBS Frontline and OPB, the NPR affiliate station in Portland, Ore. He grew up in Beaverton, Ore. and graduated from the University of Oregon.