Who was Boris Berezovsky again?

A self-made billionaire—at the height of his wealth in 1997, Berezovsky’s estimated worth was $3 billion, according to Forbes—a former academic who, after the privatization of the Soviet Union’s state-run economy, built his fortune with investments in oil, cars, airplanes, aluminum, and TV stations. Berezovsky played an integral part in Vladimir Putin’s rise to power in 2000. Once elected, Putin lashed out against oligarchs, charging many with tax evasion. In 2000, Berezovsky fled to England, where he lived until his death.

oligarchs

What happened?

On March 23 he was discovered in a bathroom at his home in Ascot, Berkshire, by his bodyguard and pronounced dead by paramedics shortly after. The Thames Valley Police reported that Berezovsky was found with “a ligature around his neck and a piece of similar material on the shower rail above him,” and the death was “consistent with hanging.” But there was no suicide note, and, according to the police, the involvement of a second party “cannot be completely eliminated, as tests remain outstanding.” Nikolay Glushkov, a longtime friend of Berezovsky and a fellow Russian exile, suspects foul play. “The idea that he would have taken his own life is bulls- – -,” Glushkov told the Guardian. “Berezovsky had a lot of powerful enemies,” says Mark Galeotti, a professor at the Center for Global Affairs at New York University. One name that’s mentioned repeatedly is Putin’s.

Why would Putin want him dead?

Putin wasn’t a fan of oligarchs in general. “Putin understood that oligarchs were truly king-makers,” says Galeotti. “And a king-maker could easily become a king-breaker. So he set out to either force the oligarchs to submit to the Kremlin, or destroy them.” Oligarch Mikhail Khodorkovsky was arrested in 2003 on charges of fraud and sent to a Siberian prison camp, where he remains to this day. Others, like Berezovsky, fled the country and found political asylum in Britain. The Kremlin continued to pursue him, seeking his extradition for crimes ranging from money laundering and financial fraud, and Berezovsky taunted them from afar, speaking publicly about Putin’s so-called “major crimes in Russia.” Now, that doesn’t necessarily mean that Putin wanted him executed. But Putin loathed Berezovsky almost as much as Berezovsky loathed him, and the mutual hatred has provided plenty of fodder for conspiracy theories.

Berezovsky had money problems at the end. How’d he lose all that cash?

Berezovsky’s second divorce in 2011 cost him roughly $154 million. In August he lost a legal battle against his former business partner, Roman Abramovich, whom he accused of blackmail and breach of contract in coercing him to sell his stake of their oil company, Sibneftegeofizika. The judge awarded Abramovich $5.6 billion and called Berezovsky “dishonest.” Berezovsky gave a final interview with Forbes the day before his death, saying, “I’m 67 years old. And I don’t know what I should do from now on.”

Berezovsky was found in his bathroom with the door locked from the inside. Even if, hypothetically, he had been murdered, how would his assassins have escaped?

“This is why Agatha Christie made so much money,” says Peter Earnest, the Executive Director at the International Spy Museum in Washington, D.C., and former CIA operations officer. “The locked room mystery is a classic fiction scenario. Is it possible to duplicate in real life? Absolutely.” It wouldn’t be the first time, Earnest says, that assassins have attempted to make a death appear self-inflicted. “That’s happened repeatedly,” he says. “People have faked accidents all the time.” Attempted assassinations are rarely as obvious as it was with German Gorbuntsov, the Russian banker living in London who was shot six times on his doorstep in March, 2012 (he survived the attack). “The possibilities are quite large when you’re dealing in the field of political chicanery and post-Cold War politics in Russia,” says Earnest.

Has a Russian oligarch ever been murdered, or is it all speculation?

At this point, it’s speculation. But more than a few oligarchs have died under mysterious circumstances. In December 2007, Georgian billionaire Arkady “Badri” Patarkatsishvili—who, like Berezovsky, initially supported Putin and went into exile after Putin’s election—told the Sunday Times there was an assassination plot against him orchestrated by the Kremlin. He allegedly had tapes of two men, one a Russian official, discussing how to make Patarkatsishvili “disappear completely.” A hit squad of four Georgians, he said, had been sent to London “to do something against me.” He died a little more than a month later at his Surrey mansion of what pathologists concluded was a heart attack. In November 2012, Russian whistle-blower Alexander Perepilichnyy, who had been helping Swiss authorities uncover a money-laundering scheme by Russian officials, dropped dead while jogging outside his Surrey home, also of an apparent heart attack. “Too many bodies are happening,” Glushkov told The Guardian recently. “I would say this is a little bit too much.”

It sounds like Russian oligarchs are justified in feeling paranoid.

Galeotti thinks they’re not quite the sitting targets they sometimes claim to be. “Oligarchs don’t lack for very extensive security,” he says. “They’re very well protected, and it’s not an easy thing to get to them.” But the late Patarkatsishvili didn’t feel especially secure. As he told the Sunday Times in 2007, “I have 120 bodyguards but I know that’s not enough.” Berezovsky had plenty of evidence that he should probably look over his shoulder occasionally. In 2007, Scotland Yard allegedly advised Berezovsky to leave Britain because of a possible assassination attempt. And in 1995, Berezovsky was nearly killed in a car bomb. He survived, but his bodyguard lost an eye and his chauffeur was decapitated.

Will we ever know the truth about any of these guys?

Pathologists are working on Berezovsky’s toxicology and histology tests, which could take weeks. “If the authorities are looking hard,” Galeotti says, “they’ll find out if there are traces of poison.” Both journalists and conspiracy theorists on the Web, have pointed out that sodium fluoroacetate, a chemical used in pesticides, can cause heart failure and is difficult to identify. Earnest thinks these conspiracies don’t go away because sometimes they turn out to be true. “Truth is stranger than fiction,” he says. “Watergate sounded like a conspiracy theory before it got uncovered. Rupert Murdoch hacking into phones of 13 year old girls? Who would believe something like that? These Russian oligarchs dying in suspicious ways may sound like the plot of spy novels, but you never know.” He personally believes, based on what he’s read, that Berezovsky probably committed suicide. “But I may be proved wrong,” he says.

(This story originally appeared, in a slightly different form, in Bloomberg BusinessWeek.)