ET3D: Hey, no fair. You said an older movie, and Tron came out a month after Blade Runner, according to Wikipedia. I thought about that movie but dismissed it because of what you said.
(Though I'm okay with not winning. It wouldn't have been my first guess anyway.)
Sorry for the confusion, I didn't mean "older than Blade Runner", I just meant older in general. And I wasn't thinking of Blade Runner specifically for my "replicants" answer, but rather the original Philip K. Dick novel. I'm a huge PKD fan, and the novel contains a lot of things, such as the "you are the messiah" surrogate religion, which weren't in the film but which fit into the artificial-ised landscape of that future world.
Again, my apology, I didn't intend to mislead with ambiguous wording.