In late 1981, director Ridley Scott showed Philip K. Dick an early cut of Blade Runner. Dick, who authored the book Do Androids Dream of Electric Sheep? — on which Blade Runner was based — said, “You would literally have to go five times to see it before you could assimilate the information that is fired at you.” A richly textured mashup of Raymond Chandler–esque noir and dystopian nightmare, Blade Runner tells the story of a detective who hunts down and retires advanced androids called replicants. Like all great science fiction, the film asked big questions, like, What does it really mean to be human? (And slightly smaller questions like, Is Harrison Ford a robot or not?) Blade Runner baffled test audiences in early 1982, causing the studio to add a voice-over narration and change the ending, using leftover shots from Stanley Kubrick’s The Shining. To date, seven different versions of the film have been shown, and if that isn’t cause for confusion, we don’t know what is.