After spending a year in prison, Bitcoin pioneer Charlie Shrem has a new job and a new mission: Strengthening the ecosystem of blockchain assets—and, just maybe, helping build the future of the Internet. “My word is gold,” says Charlie Shrem, glass of absinthe in hand, light winking off a pinkie ring he wears that is embossed with a Bitcoin symbol. “And I make sure everyone gets paid.”

Bitcoin’s first felon is in his favorite mode: full-on bluster. We’re in Sarasota, where he lives, perched on stools at Pangea Alchemy Lab, a faux-speakeasy tucked behind a curtain in the back of a sandwich shop. The bartender is a bearded anarchist who, after making our drinks—he drips water from a sort of four-armed decanter onto sugar cubes suspended on slotted spoons above glasses of French absinthe—asks if I’ve read Debt: The First 5,000 Years, by the anthropologist David Graeber. Shrem has been offering plenty for the bartender to eavesdrop on, a discourse that features words like Bitcoin, blockchain, digital currency.

Before his fall from grace, Shrem was living the high life as a Bitcoin millionaire. Now, at 27, he once again has something to prove. Ten months after his release from federal custody, he has a new job, and he’s looking to mount a comeback.

It’s happening just as digital currencies are in the midst of an epic explosion. Bitcoin and its ilk are now worth $107 billion, six times their value at the beginning of the year. It’s either the beginning of a global financial realignment—or a bubble of historic proportions. These days as much as $6.6 billion in digital tokens changes hands every day, and even mainstream players such as Goldman Sachs (GS, -0.06%), Visa (V, -0.34%), Capital One, Nasdaq, and the New York Stock Exchange have invested in the underlying technology.