About a year ago, the renowned and often-successful short-seller Marc Cohodes began to get very suspicious about Sam Bankman-Fried, his crypto exchange FTX, and his hedge fund Alameda Research. At the time, S.B.F. was at the height of his prowess. FTX was valued at $32 billion and S.B.F. was worth around $25 billion on paper. He was being compared to Warren Buffett and J.P. Morgan. He was on the covers of Fortune and Forbes, both of which hailed him as the second coming. But for Cohodes, there was “something terribly wrong” about the S.B.F. narrative. “It makes no sense,” he told me a few weeks after FTX filed for bankruptcy, but before S.B.F. was arrested and extradited to the United States.  

The small but often contentious world of short-selling is filled with fractious argumentation, often on social media. And so by late spring, Cohodes took to Twitter, where he has more than 130,000 followers, and started going after S.B.F. In June, he tweeted, “The best short on the board right now is Sam Bankman-Fried and FTX.” This was a little tongue-in-cheek, of course, given that FTX was a private company and there was no stock or traditional security to short. “Sometimes I do things just to help society out,” he told me, “just to try to rid the world of bad guys… I don’t stand to make a buck from it. But sometimes you do things to help people out. It’s not always about making a buck.”