Seven months ago, Chinese police detained the country’s most prominent artist, Ai Weiwei, at the airport and drove him to a hidden location. It was the beginning of a two-and-a-half-month nightmare for the architect and sculptor, a former darling of the Communist Party turned outspoken government critic. Ai was held on vague -charges of economic crimes, kept in isolation, and submitted to Kafka-esque interrogations. Determined to maintain his wits, Ai tried to memorize every detail of his detention. “But after 20 days, my brain became completely empty,” he says, disclosing the fullest account yet of the grim conditions of his confinement. Cut off from the outside world, in a featureless cell, his mind began to panic. “I realized you need information to stay alive. When there’s no information, you’re already dead. It’s a very, very strong test—I think more severe than any physical punishment,” Ai says.