In news photos showing the four Americans released from prisons in Iran this month, one man appears only as a silhouette: Nosratollah Khosravi-Roodsari. There is no known photograph of him, and that name doesn’t show up in several public record searches. Khosravi himself doesn’t appear to have a social media account. He is as close to anonymous as one can be today.

But based on interviews with current and former officials who know some of the details of Khosravi’s case, a picture is emerging of the mysterious fourth man, and not a flattering one.

Khosravi, who has been described as a businessman specializing in the design and sale of carpets and rugs, may also have been an ambitious huckster with an overeager imagination and a penchant for telling wild stories—tales that landed him in an Iranian jail.

While visiting family in Iran last year, Khosravi, who has Iranian and U.S. citizenship, claimed that he was working for the FBI, and that he had information on the whereabouts of Robert Levinson, a retired FBI agent and contractor for the Central Intelligence Agency, who was kidnapped in Iran in 2007 and hasn’t been found.

It was a wild claim, especially since he had no such information.

The three other Americans who were freed along with Khosravi, including Washington Post reporter Jason Rezaian, had all been accused of working with American intelligence or trying to subvert Iran’s national security, and all three firmly denied the allegations.

But here was Khosravi, not only telling various people in Iran he was an agent of the United States, but that he had information about Levinson, who has been the subject of intense negotiations between U.S. and Iranian officials for years.

Khosravi was taken into custody last year and questioned about his supposed connections to the FBI and Levinson. How the Iranians became aware of his astonishing claims is unclear. But two U.S. officials told The Daily Beast that this much is certain: Khosravi was making it all up.

“He never worked for the FBI in any capacity,” one official told The Daily Beast, speaking on condition of anonymity when discussing Khosravi’s very sensitive case. He wasn’t a consultant, an adviser, or an employee. Officials don’t deny Khosravi appears to have been peddling his story in Iran. But they insist it wasn’t true.

The FBI came to the conclusion that Khosravi knew nothing about Levinson after Khosravi himself called the bureau, sometime before he left for Iran, and claimed to have information on the missing American. FBI officials interviewed him and found Khosravi’s claims weren’t credible, the official said.

Suzanne Halpin, Levinson’s sister-in-law and a spokesperson for the family, told The Daily Beast that they’d never heard of Khosravi until his release from Iran, nor were they aware of him ever saying he had information about Levinson.

Why Khosravi chose to pass himself off as working for the FBI is still a mystery. The Iranians might have marveled at their own good luck in snaring a potential American agent. But they don’t seem to have believed Khosravi’s story either.

Nine months ago, U.S. officials first learned that Khosravi was in Iranian custody when they were “alerted to his presence by Iranian authorities,” another U.S. official told The Daily Beast.

At the time, Obama administration officials and their Iranian counterparts were already five months into secretive negotiations aimed at freeing the other three American captives in a prisoner swap with Iran. Khosravi was added to the mix, but still never publicly identified by either side.

That was the opposite of Iran’s behavior in the cases of the three other American prisoners, the Post’s Rezaian, former U.S. Marine Amir Hekmati, and Christian pastor Saeed Abedini. Iranian officials trumpeted their arrests and made baseless accusations of espionage. Their cases were also reported in official media.

But Khosravi’s name never appeared in print in Iran, and there is no record of him ever having been charged or tried. It was as if the Iranians were more interested in getting rid of him than exploiting him.

Some details about Khosravi’s case emerged last weekend when IranWire, a publication run by former Iranian prisoner Maziar Bahari, ran a story about Khosravi’s alleged FBI connections. The details were attributed to Khosravi’s former cellmate in Iran’s Evin Prison, and an unnamed family member, but the publication was unable to reach Khosravi himself.

Current and former officials said it was possible that Khosravi told his cellmate or family members and friends that he worked for the FBI, but that doesn’t make it true.

IranWire, which partners with The Daily Beast, reported that during a night out drinking with friends in Iran, Khosravi texted an FBI contact he had met in the United States, either in Florida or California, who had been looking into Iranian involvement with car theft rings.

Khosravi said in the SMS that he knew Levinson’s whereabouts. Iranian security intercepted the text and picked Khosravi up for questioning as a result, but he claimed that he’d been lying to impress his FBI contact and was under the influence of alcohol when he sent the text, IranWire reported.

The U.S. official who said that the FBI had previously interviewed Khosravi said that he took the business card of one agent. The official did not know if Khosravi ever tried to contact the agent.

The Daily Beast was unable to reach Khosravi to hear his side of his improbable tale. His whereabouts are unknown, but a U.S. official said that he has left Iran.

After the prisoners were released from jail, Khosravi turned down a seat on a Swiss aircraft on Jan. 16 that ferried the three other American prisoners to Europe. (They are now all back in the United States. An American student whose case was unconnected to the prisoner swap and who had been held in Iran for 40 days also was freed.)

Khosravi’s mother and other family members live in Iran. He may have gone to stay with them before finally leaving. Where he goes next is another mystery.