Greed, said the awful Gordon Gekko, is good. When I was trapped in a multi-billion-dollar global fraud, I was shocked to find that it was also insatiable. Even super-rich financial hoodlums want more and are threateningly impatient to get it.

My life isn’t cosmopolitan, or even metropolitan, by any stretch. I live in a small place in western Scotland, where I happily care for my family. When my father died, in 2015, and left me a small inheritance of $15,000, I wanted a secure investment, especially for my two grandchildren.

My best friend introduced me to OneCoin, Ruja Ignatova’s magical crypto-currency, which would make my cash multiply and troubles vanish. Only it was my money that would disappear—and almost $300,000 belonging to my friends and family—adding to the more than $4 billion she swindled. Even now, during the summer of 2023, in a remote corner of the globe, Ignatova’s OneCoin will, without a glimmer of humanity, steal a family’s future, a child’s education fund, the payment of life-saving hospital treatment, and, as likely, the money for tonight’s dinner.

In 2017, I pledged to bring down the wicked woman behind OneCoin and her evil accomplices, including her co-founder, Sebastian Greenwood, who, on September 12, was sentenced to 20 years in prison for his role in the fraud. I’m proud of my activism. Tens of thousands of her victims helped put her on the F.B.I.’s 10 Most Wanted list and gave inside information for the agency’s investigation, which led to the arrests of her fellow scammers. I wrote my book, Devil’s Coin, as a warning to others.

It wasn’t easy. When I first set up the victims’ support group in 2017, it attracted vile abuse, death threats, and threats of lawsuits from Ignatova, who hired the best lawyers. Then, also in 2017, she vanished and became an international fugitive. Later that year, Europol revealed that OneCoin was backed by Moscow and Eastern European Mafia groups full of dead-eyed villains. Ignatova’s crypto-currency was revealed to be a money-laundering scheme linked to international terrorism.

These revelations, plus the personalized intimidation against me, were frightening. But as it all increased, so did my very Scottish anger. I wasn’t having any of it.

I always return to a story told to me by an OpenCoin whistleblower. Ignatova sat behind a huge desk at the OneCoin offices in Sofia, Bulgaria, every Monday morning during the glory days of the fraud. She openly burned the account books, which registered the money that had been generated the previous week and was brought to her offices at 10 A.M., not a moment later. Meanwhile, millions of dollars were packed into suitcases. As the men carrying the suitcases left, she would smile and say, “See you next Monday.”

At the same time, Ignatova’s brother, Konstantin, was plundering the poor in Uganda while her co-conspirators stole throughout Europe, Asia, China, South America, Australia and New Zealand, and America.

Europol revealed that OneCoin was backed by Moscow and Eastern European Mafia groups full of dead-eyed villains.

Those at the top of the OneCoin pyramid made so much money that they piled up cash in offices and apartments in Bulgaria, Hong Kong, Dubai, and South Korea before it was “washed” through America and Europe. Ignatova boasted of working on five continents and operating in more than 190 countries. For once, she was telling the truth: the world was her target.

Sometimes the money circulated between European banks, withdrawn in small bills, deposited in a Western Union office, sent by the bank over the Mediterranean Sea, received in cash by an intermediary in Dubai, and finally deposited directly to a sanitized account. That’s where the real money went before it was transferred back through Singapore and Hong Kong and back into America, going through U.S. banks from coast to coast. Truly, it was a financial soap opera.

When I worked behind the bar in pubs, there was always the problem of staff pilfering a few pounds or a bottle of whiskey. With OneCoin, one partner stole $10 million, and it was treated as a trifle, no more than an annoyance.

Finding out what they did with the stolen funds was like sinking into quicksand. On a 2017 visit to the OneCoin offices in Hong Kong, Ignatova took rooms at the five-star Ritz-Carlton hotel, in Kowloon. There, she summoned her office manager, an assistant, two Russian bodyguards, and a backpack containing $100,000 in cash. She wanted to “do a little shopping” and took off to the Elements shopping mall.

She bought expensive clothes and “trinkets” to contrast the sparkle of her $1 million jewels, which she bought “on mad afternoons” in Dubai, where she had her spectacular eighth home, a $20 million manse. She kept her Rolls-Royce in Dubai and the Bentley in Sofia, along with an armored Lexus and a couple of Porsches. Such displays of wealth did not trouble the authorities in Bulgaria. In fact, the police often collected Ignatova’s guests from the airport.

Ignatova is still on the run. I hope the next time she visits New York it will be in handcuffs courtesy of the F.B.I., who, in July, increased the reward for information about Ignatova’s whereabouts to $250,000. That will be money well spent.

Jennifer McAdam’s Devil’s Coin: My Battle to Take Down the Notorious OneCoin Cryptoqueen is out now from William Morrow