The hotel was 29 stories of gentle curves and ribbons of blue glass, reaching toward the clouds in the heart of Bangkok. It was called the Athenee and had been built on the grounds of a former royal palace.

And on this early summer day in 2017, a handful of U.S. federal investigators, representing an alphabet soup of agencies, were hunkered together in the hotel’s lounge, thousands of miles from the drab government offices where they normally worked. That they’d made it to Thailand, to a building brimming with five-star opulence, was a testament to the years they’d devoted to identifying and locating the mastermind behind AlphaBay, a dark web emporium where customers spent millions of dollars in cryptocurrency on drugs and other illicit pursuits.

The feds had found their man—a twenty-something Canadian named Alexandre Cazes, who had amassed a $24 million fortune—and were planning to arrest him, and shutter AlphaBay, in a few days’ time.

Cazes had believed his digital footprints were untraceable.

The authorities were confident he’d never see them coming.

But then one FBI agent at the Athenee spotted Cazes; he was headed right toward their table. Was Cazes—who used his crypto wealth to zip around like a Bond villain in slim suits and a Lamborghini, and secretly record unsuspecting women with whom he had sex—about to pull the rug out from under the feds?

“Oh shit,” Grant Rabenn, then a federal prosecutor, thought. “This thing’s over.”

This stylish cat-and-mouse scene is a small glimpse of some of the dramatic stories in Tracers in the Dark: The Global Hunt for the Crime Lords of Cryptocurrency. Written by Andy Greenberg ’04, the book is a taut exploration of a hidden universe, one where criminals, law enforcement, and private sector puzzle-solvers scramble to decipher and harness the power of digital currencies and the blockchain, an unalterable public ledger that records cryptocurrency transactions.

The stakes are dizzying: North Korean hackers are estimated to have stolen more than $2 billion from cryptocurrency exchanges since 2017, propping up Kim Jong-un’s dictatorship, and other corners of the dark web have become a haven for predators creating and sharing child pornography.

Few know the crypto landscape as well as Greenberg, now a senior writer for WIRED. In a 2011 story for Forbes magazine, he became one of the first mainstream journalists to introduce readers to the then-nascent cryptocurrency Bitcoin, which was launched in 2009.

One of the first Bitcoin programmers spoke loftily at the time about the promise of a decentralized, and entirely digital, currency: It couldn’t be controlled or seized by banks or governments, and purchases would remain anonymous. “This is, like, better gold,” the official crowed, “than gold.”

It didn’t take long for opportunists to start populating the crypto Wild West. Some sought riches from exploiting others’ addictions; others viewed themselves as idealists who were building new marketplaces and communities, free from government meddling. (It is estimated that more than 9,000 different cryptocurrencies now exist, with Bitcoin and four others dominating what’s become a volatile marketplace.)

The villains in Greenberg’s book took it as a matter of faith that their finances could never be tracked, that their identities and IP (internet protocol) addresses—which could reveal their locations—would remain cleverly obscured.

“They each, in their own way, believed they were perfectly anonymous and untouchable,” Greenberg says. “And that creates incredible dramatic irony, to watch these people who believe that they’re getting away with living their freest, most liberated lives. They’re becoming who they want to be, in the ways that people do when they think no one is watching.”

Greenberg was struck, in crypto’s early days, by the conflicting forces that would one day animate his book: a reasonable desire for people to have some measure of digital privacy in an era of growing surveillance, and the likelihood that any effective tools for anonymity would be abused.

A few months after Forbes published Greenberg’s first story on Bitcoin (the first cryptocurrency to appear), U.S. senators Charles Schumer and Joe Manchin demanded federal authorities shut down a site on the dark web that few Americans had heard of: the Silk Road. But after the senators explained how visitors could easily download software—called Tor—that encrypts a user’s web activity, and use Bitcoins to purchase cocaine, heroin, and other drugs from the site, Silk Road’s customers multiplied from hundreds to thousands.

In 2013, Greenberg managed to persuade Silk Road’s administrator, a self-styled libertarian revolutionary who went by the nom de plume Dread Pirate Roberts, to participate in a five-hour interview, conducted on the site’s messaging system. Silk Road’s revenue had by then soared to almost $45 million.

“What we’re doing isn’t about scoring drugs or ‘sticking it to the man.’ It’s about standing up for our rights as human beings and refusing to submit when we’ve done no wrong,” Roberts told Greenberg.

Later that year, the FBI arrested Roberts—real name, Ross Ulbricht, 29—at a public library in San Francisco. Prosecutors connected drugs sold on Silk Road to at least six fatal overdoses and estimated the site had grossed $200 million in sales. Ulbricht was convicted of seven offenses, including continuing a criminal enterprise, a charge usually reserved for the heads of organized crime, and received two life sentences.

In a twist that seems fit for a pulpy series on a streaming service, Carl Mark Force, a federal undercover agent assigned to the Silk Road investigation, also ended up behind bars, convicted of embezzling nearly 1,000 Bitcoins from Ulbricht and FALL 2022 39 40 Haverford Magazine Tracking the Crime Lords of Cryptocurrency lying about the transactions in government records.

Greenberg tells the story of Force’s misdeeds through the eyes of Tigran Gambaryan, a young, analytical IRS investigator who methodically builds a case against Force by combing through the Bitcoin blockchain, which hides users’ identities behind pseudonymous addresses.

It is tedious work, devoid of pulse-pounding foot chases, and in the hands of a lesser writer, the digital digging could easily cause the narrative to lose steam. But Greenberg writes with a deft hand, and never allows the pace to lag. Nor does he let readers lose sight of the fact that serious and sometimes horrific crimes—some with global implications—are unfolding throughout, even if they’re committed with the subtle thrum of fingers tapping on laptop keyboards.

Gambaryan is part of a large cast of federal authorities who rotate in and out of the different cases recounted in Tracers in the Dark, and Greenberg acknowledges he was wary of relying too much on the law enforcement perspective. “That’s often not the most nuanced view, as you can imagine,” he says.

He finds balance in other characters who are drawn to cryptocurrencies because they represent a riddle begging to be solved. Greenberg refers to one, Sarah Meiklejohn, as the book’s conscience.

Meiklejohn, then a graduate student at the University of California, sought to test whether the idea of Bitcoin anonymity was just wishful thinking. She made hundreds of her own Bitcoin purchases in 2013, and studied a database filled with millions of purchases that had been recorded on Bitcoin’s blockchain. Amid the tangles of seemingly incomprehensible data, Meiklejohn detected digital trails that enabled her to trace the path of any transaction—from seller to buyer—even when the money traveled a circuitous route.

To a person with patience and an analytical mind, Bitcoin was about as transparent as a credit card receipt. What followed Meiklejohn’s discovery was a sort of dark web arms race: Criminals sought more elaborate means of disguising their identities and operations, and law enforcement agencies turned to a private startup, Chainalysis, that was pioneering methods of unmasking their targets.

Digital sleuthing would become an even bigger business model than the illegal operations that authorities wanted to topple. Alexandre Cazes was ultimately arrested in 2017— after coincidentally crossing paths in that Bangkok hotel with the agents who were plotting his downfall—and died by apparent suicide in a Thailand jail. Federal officials claimed AlphaBay had more than 200,000 users and processed more than $1 billion worth of cryptocurrency transactions. Chainalysis, which played a critical role in the government’s AlphaBay investigation, as well as a later probe of a ransomware attack that crippled a U.S. gasoline distribution company, is now worth more than $8 billion. Some of the investigators who appear throughout Greenberg’s book have since taken jobs in the private sector.

“The pull of the crypto world is just enormous,” Greenberg says. “There is so much money sloshing around.”

It would have been easy for Tracers in the Dark to veer into commentary. In addition to a decade’s worth of beat reporting that formed the book’s foundation, Greenberg, 40, also has written two other books: Sandworm: A New Era of Cyberwar and the Hunt for the Kremlin’s Most Dangerous Hackers, and This Machine Kills Secrets: How WikiLeakers, Hacktivists, and Cypherpunks Aim to Free the World’s Information. To call him an expert is something of an understatement. Yet Greenberg largely shied away from inserting himself into Tracers’ narrative.

“You don’t want to bog anything down with your own opinions,” he says. Instead, he preferred “to just tell these stories, because they’ve never been told before, and some of them are almost too crazy to believe.”

Away from the page, though, Greenberg admits to being somewhat conflicted by some of the ethical quandaries that his book introduces. “Bitcoin was interesting in part because it seemed like it was an antidote to financial surveillance. That’s a real problem it was trying to solve,” he says. “Cash is going away, in so many respects. And credit cards and PayPal and Venmo are deeply unprivate.”

But privacy, he notes, is a complicated thing. In the wrong hands, it’s a shield for abhorrent behavior. A father of two, Greenberg was particularly haunted by the details of an investigation that Gambaryan, the IRS agent, launched into Welcome to Video, a South Korea-based dark web site that sold access to child sex abuse images and videos in exchange for Bitcoin.

The case resulted in hundreds of arrests, and led to 23 children—including the stepdaughter of a U.S. Border Patrol agent—being removed from sexually exploitative situations. “It definitely changed my view of the worst things that people are capable of,” Greenberg says.

The ability of companies like Chainalysis—and the government—to circumvent the increasingly advanced defenses that criminals hide behind seems, in some cases, righteous, he says. But Meiklejohn warns in the book that those same capabilities could easily be used by authoritarian governments to snoop on their citizens.

“Sometimes I don’t know myself what to think,” Greenberg says. “It’s a really complex topic.”

No blockchain-esque analysis is needed to decipher the path that led Greenberg to Tracers in the Dark, to being an accomplished journalist and author. He just points back to Haverford College.

He didn’t discover an interest in journalism until he neared the end of his time at the school. A Center for Peace and Global Citizenship fellowship enabled him to travel to China and dabble in freelance writing.

“In the spirit of liberal arts,[Haverford] emphasized intellectual exploration,” Greenberg says. “And that does really prepare you to get really interested in complicated things. That’s kind of a superpower for a journalist.”

His road ahead will include more reporting for WIRED; a recent story revealed that AlphaBay, the notorious digital drug market, has been resurrected. Greenberg landed an interview—conducted via encrypted instant messages— with its new administrator, a figure known only as DeSnake, who claimed the site is once again the dark web’s top destination, offering everything from opioids to stolen Social Security numbers.

And the world of Tracers in the Dark will soon be expanded and introduced to a wide audience, including viewers and listeners whose knowledge of cryptocurrency might be limited to some awful Super Bowl commercials. Earlier this year, the Hollywood Reporter wrote that Jigsaw Productions, part of Imagine Entertainment—the company founded by director Ron Howard and producer Brian Grazer—plans to adapt the book into a podcast, documentary, and scripted show.

“I do think most people know what the dark web is now,” Greenberg says. “I don’t think most people who were first involved in Bitcoin cared about its privacy properties. The vast majority of people buying Bitcoin saw it as an investment vehicle, to get rich quick.

“Today, the average person, I don’t think they care about Bitcoin privacy. Maybe they don’t care about privacy in the first place.”

He pauses for a beat.

“I mean, you see what people are willing to give to Facebook, right?”