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Released in (1982), Blade Runner is a very dark science fiction film directed by Ridley Scott. Based loosely on the novel Do Androids Dream of Electric Sheep? by Philip K. Dick, it presents a bleak dystopic vision of Los Angeles in the not too distant future.
Harrison Ford stars as Rick Deckard, the Blade Runner called out of retirement to track down and "retire" (kill) several "Nexus-6" replicants who are illegally present on earth. Rutger Hauer and Darryl Hannah play two of the fugitive replicants, and Sean Young plays Rachael, Deckard's love interest whose own humanity is in question.
Six versions of the film exist but only two are widely known and seen; the original theatrical release ((1982, also called domestic cut), and the Director's Cut (1991). The latter does not include Deckard's explanatory voice-over and a scene was both added and removed. The added scene is a dream Deckard has when he's dozing off at home drunk playing the piano. It shows a unicorn running through a forest. The removed scene is the ending, where Deckard and Rachael are driving off into the wilderness.
Ridley Scott decided both the voice-over and the happy ending were not suited to the movie. The ending in the Director's Cut has to do with the included scene: Deckard picks up a small origami unicorn he noticed on the ground when it was knocked over by Rachael when she was walking towards the elevator. This suggests Gaff knew about his dreams, insinuating Deckard too has fabricated or copied memories, making him a replicant as well.
The other four versions include two workprint versions shown only as previews to test audiences' response, these have occasionally popped up at film festivals in later years. The remaining two are the international cut and the broadcast version. Both basically the same as the original theatrical release, but the former contains more graphic violence and the latter has some cursing removed.
Two Blade Runner novels, sequels to the movie, have been written by K. W. Jeter:
There is also a PC game, based on on the world described by the film.