When I began my search for the most mysterious figure in tech, I never expected to find myself in a room full of severed human heads. And yet that’s exactly where I ended up, in a state-of-the-art facility in Phoenix, Arizona, surrounded by giant metal cylinders filled with liquid nitrogen, wondering if one of them contained the frozen remains of Satoshi Nakamoto. Satoshi is the pseudonymous creator of Bitcoin, the world’s first cryptocurrency.