This novel, first published in 1968, was the basis for Ridley Scott's film Blade Runner (1982), which despite its striking, evocative visuals, plucks elements of the novel out of their context, making them somewhat less intelligible and less radical than in the original. Additionally, Dick's humor and his metaphysics are missing from the movie. The reader of the book is continually challenged to evaluate how human the androids are and how mechanical the humans are. The androids are not mere machines like most of the simulacra in Dick's other novels: they are artificial people made from organic materials; they have free will and emotions like fear and love. Physically and behaviorally they are indistinguishable from real people. Rick Deckard is a bounty hunter whose job it is to hunt down and kill escaped androids. His life is thoroughly programmed; but in the course of the novel he starts to wake up to his buried human nature and capacity for empathy and understanding. This novel is the place to look for a serious analysis of the question of what it means to be human; you get only the tip of the iceberg of that issue in the movie. The book is one of Dick's best.