Do Androids Dream of Electric Sheep?

Book excerpt: By 2021, the Terminus War had driven mankind off-planet and entire species into extinction. Now only the rich can afford living creatures; others may buy amazingly realistic simulacrae: horses, cats, sheep ... Even humans. These artificial people are so advanced it's impossible to tell them from true men and women--except for their lack of empathy. Without empathy, androids can--and do--kill their owners and blend into society, so they're illegal on Earth. It's Rick Deckard's job to find these rogues and "retire" them. But "andys" tend to fight back--with deadly results.