In Los Angeles in November 2019, ex-police officer Rick Deckard (Harrison Ford) is detained by officer Gaff (Edward James Olmos) and brought to his former supervisor, Bryant (M. Emmet Walsh). Deckard, whose job as a "Blade Runner" was to track down bioengineered beings known as replicants and "retire" (a euphemism for killing) them, is informed that four have come to Earth illegally. As Tyrell Corporation Nexus-6 models, they have only a four-year lifespan and may have come to Earth to try to extend their lives.