Philip K. Dick's Do Androids Dream of Electric Sheep?, often referred to as Blade Runner, introduces Rick Deckard, a bounty hunter tasked with "retiring" (killing) rogue androids that have escaped to Earth from Mars. The narrative follows Rick's moral and psychological struggles as he confronts increasingly human-like androids, particularly the advanced Nexus-6 models, and questions the distinction between humans and artificial beings. Key elements include the Voigt-Kampff Empathy Test, used to identify androids, and the pervasive post-apocalyptic environment of Earth, where real animals are rare and highly valued, and Mercerism, a prevalent religion offering shared suffering and transcendence. Rick's encounters, including a manipulative android named Rachael Rosen and a fellow bounty hunter named Phil Resch who might also be an android, force him to re-evaluate his perceptions of life, empathy, and his own humanity. The story explores themes of existentialism, artificial intelligence, and the nature of consciousness in a decaying world.