George Orr's dreams have the ability to change the world. I mean this in the most literal sense--he's not a go-getter with big plans for the world. In fact, he's nothing short of ordinary. George literally has dreams that change reality. 
 No one would believe that he has this ability. He wants to do everything in his power to stop it. When he visits Dr. Haber, the psychiatrist plays him off as another psychotic patient--or so it appears. But when George undergoes hypnosis, which apparently is intended to help suppress his dreams, he's starting to discover that Haber is feeding him dreams intended to alter reality. And there's no one he can trust to rat him out, because who would take the word of a psychiatrist patient over the word of his doctor? 
 The shift is subtle. There are times through the story when you're not sure whether it's reality, or whether George is dreaming. George can't do anything to alter his own dreams, which gives Haber full reign of his power through hypnosis. And who wouldn't want to improve this overcrowded, war-ridden, poverty-stricken society? With George's skill, anything is possible. 
 It's brilliant because there's no clear cut "right and wrong." Haber's utopia sounds ideal, after all--no war or racism? No overpopulation problem? But George sees it a different way. Every time he dreams the entire scope of reality changes, but what happens to the old reality? He and Dr. Haber are the only ones who remember the old realities. To the rest of the world, it's as if they never occurred. 
 The end is just... brilliant. Is the end result good or evil? Is this the utopia Dr. Haber desired or not? But with all the "utopia" tales out there, there's something not right with the society. Makes you wonder what you're willing to sacrifice for the sake of a perfect world, and whether that sacrifice is worth it.