The main plot follows Rick Deckard, a bounty hunter who is faced with "retiring" six escaped Nexus-6 brain model androids, the latest and most advanced model, while a secondary plot follows John Isidore, a man of sub-par IQ who aids the fugitive androids. In connection with Deckard's mission, the novel explores the issue of what it is to be human. Unlike humans, the androids possess no sense of empathy. In essence, Deckard probes the existence of defining qualities that separate humans from androids.

Although frequently omitted from cyberpunk reading selections, the empathy machine and the androids themselves warrant the genre's umbrella to shade Dick's remarkable dystopian vision.