Almost a decade & a half earlier before Blade Runner, 2001: A Space Odyssey was one the first films to successfully marry the big budget sci-fi with a genre of a different theme (that of psychological thriller) so that all the high tech flashiness of science fiction acted as a contrasting backdrop to a darker side that resided underneath all the complicated buttons & wires of futuristic technology.
Then came Ridley Scott's Alien, which did the same for the darkside of sci-film, but now more in the method of the straight-up horror genre.
He followed that up with another marriage to sci-fi, but this time in the cinematic category of film noir. Now, with this story of replicant-hunter Rick Deckard, Scott depicts what lays beneath all the flashy neon lights that decorately symbolize the endless possiblities of the future, to tell a tale of the grit & grime layers of lost & forgotten cybo-souls that could only act as a foundation of those towering spires of technological brilliance that would allow the mortal men living in 'em to percieve themselves as gods.
Blade Runner is just as equally a visual stunner as the other famous sci-fi classic that Harrison Ford is famously known for, but now, instead of a distant galaxy far far away, it's in a distant future that more down to Earth.