Fans of true crime have as much unsolved material to investigate in crypto as in virtually any other industry. Unlike cash or bank transfers, crypto allows payment of millions of dollars within seconds and this instant and irreversible settlement of nearly unlimited sums of money makes it a perfect tool for foul play.

The massive sums of money in play also go hand-in-hand with extravagant lifestyles, risky travel, drugs, and various poor life decisions.

As a result, it’s not entirely surprising that there have been a number of high-profile deaths over the past 15 years.

Unsolved deaths of crypto leaders

Perhaps the most famous crypto disappearance is John McAfee, the creator of the popular McAfee Antivirus freemium software used on hundreds of millions of computers. After exiting that software company, McAfee became a crypto promoter and drug-addicted globe-trotter.

The tech mogul-turned-crypto bro ended up blowing most of his $100 million fortune, dying in an apparent suicide in a Spanish prison with just a few million left. However, his death remains a mystery to this day for two simple reasons.

First, it was well-known that McAfee held substantial sums of money on hardware crypto wallets while facing numerous civil lawsuits, providing a motive for faking his own death. Second, he tweeted a few weeks before his death, “Know that if I hang myself, a la Epstein, it will be no fault of mine.”

The next most famous death in crypto history is probably Gerald Cotten, the founder of Canada’s once-largest crypto exchange, Quadriga CX. After stealing hundreds of millions of dollars from customers, Cotten’s wife claims that he died in India without giving anyone the private keys to those funds.

The declaration of his death for medical reasons is curious not only for its exotic locale but also because Cotten’s QuadrigaCX bitcoin moved after his supposed death. Documentarians chronicled his career and skepticism over his death in the Netflix movie The Crypto King.

Read more: Crypto legend John McAfee’s suicide confirmed by Spanish courts

Private keys at the bottom of the sea

Mircea Popescu is another curious death. The proudly toxic Bitcoin maximalist was the 2012 (yes, 2012) founder of MPex. He supposedly died with tens of thousands of bitcoin. Media reported his net worth at around $2 billion as of the time of his accident on June 23, 2021.

According to Costa Rican sources, Popescu was swimming near Playa Hermosa and simply died in the current. However, no one has seen his remains to confirm his death.

Another swimming accident allegedly took the life of Nicolai Arcadie Muchgian, the co-founder of Maker. Maker operates one of the first ostensibly decentralized stablecoins, DAI, and manages over $8 billion in assets today. Condado and the nearby San Juan metro area of Puerto Rico is a tax haven for crypto elites, however, making his death with no remains in that area suspicious.

Bob Lee, the founder of CashApp and contributor to MobileCoin, is another troubling crypto death. Jack Dorsey gave prominence to Lee’s CashApp bitcoin exchange, and Elon Musk promoted Signal, which exclusively used MobileCoin. Lee was stabbed to death in another crypto elite hub: San Francisco.

Read more: MobileCoin founder Bob Lee’s murder was planned, prosecutors say

Other unsolved murder cases and disturbing deaths in the history of crypto include billionaire Matthew Mellon, Tiantian Kullander of Amber Group, Autumn Radtke of First Meta, Vyacheslav Taran of Forex Club and Libertex Group, Argentine crypto trader Fernando Pérez Algaba, and Javier Biosca of Algorithms Group.