He no longer accepted that this was his reality. He couldn’t. He even wondered sometimes, fleetingly, whether Amy was a dream, perhaps generated from the same place in his mind that, under the influence of ketamine, had built those minarets and mazes and phantom ships. The last time, ironically, that he could have known, really known, without a trace of doubt, where he was, was in Afghanistan, after his gunner, Jensen, had rescued him but before the morphine, when he was curled in the back of a Humvee, headed to the helicopter landing zone. In dust kicked up by other vehicles, the driver had gotten lost, and Sam had still somehow mustered enough clarity of mind and enough strength, or at least enough adrenaline, to rouse himself from the backseat, radio for coordinates, and tell the driver where to go: due south three and a half kilometers. He leaned forward to jab at the GPS with his finger. "Look, we are right here." He was just as stunned as the driver to see his own flesh smeared on the glowing screen. Outside, through the armored windshield, the last gray specks of daylight glimmered in the dust rising from the poppy fields. That was the last time Sam could have said for sure that any map in his life could correlate to one and only one world, virtual or otherwise.

He became a recluse, hardly ever leaving the house. What was interesting was that he no longer really feared pain. Not physical pain. He had chosen to be strict with himself about getting by now on lower doses of drugs. He had learned to escape into his own mind, where there was a quiet chamber awaiting him, a peaceful void without a soundtrack or flying snowballs, but also without Amy or anyone, where the pain only came through like a distant muted voice that he could choose to ignore.

Then, one evening, he and Amy sat down and watched a movie together called, of all things, Fireproof. The movie was about this firefighter and a nurse whose marriage is about to dissolve. The firefighter, played by Kirk Cameron, gets injured while saving a girl from a house fire. He’s brought to the hospital where his wife works and where she’s been flirting with a doctor who doesn’t know that she is married to the firefighter (since things had already gotten really bad, bad enough that she no longer wore her wedding band). By the time the credits rolled, Amy was sobbing.

Sam found himself suddenly panicked at the thought of losing her, the one person who had made his life bearable. If he was going to win out over self-pity, if he was going to save his marriage, he’d have to recommit to the only world that mattered. The others were all cheap phantoms. Mazes of smoke and ash. Because this world, the one with meaning, the one where he was a lucky bastard just to be alive, this world that had the deepest and most unforgiving kinds of pain that you could not even fucking believe—well, he, for one, would not have rid himself of it for anything.

Last July, Maani and Hoffman published the results of the study in which Sam Brown had participated. Echoing the civilian studies, soldiers reported significant drops in pain while immersed in SnowWorld. Time spent thinking about pain, which is an inextricable contributor to actual pain, dropped from 76 percent without SnowWorld to 22 percent with SnowWorld. Amazingly, some of the biggest drops were for the most severe levels of pain, which went against every previous expectation. Since then, SnowWorld has received a good deal of enthusiasm from several well-lit corners of the Pentagon. At least one four-star general, after seeing the results from the ISR study, has gone so far as to say that he foresees a day coming soon when VR pain distraction might become standard care. There is nearly equal excitement about Hoffman’s other applications, including one called IraqWorld, a virtual-reality exposure therapy he built to treat soldiers with PTSD.