On his first tour of duty in Afghanistan, Sam Brown was set on fire by an improvised explosive device. He survived, only to find himself, like thousands of other vets, doomed to a post-traumatic life of unbearable pain. Even hallucinogen-grade drugs offered little relief, and little hope. Then his doctors told him about an experimental treatment, a painkilling video game supposedly more effective than morphine. If successful, it would deliver Brown from his living hell into a strange new world—a digital winter wonderland