Blade Runner Is Set In The Same Universe As Alien, Predator, Prometheus, And ... Star Trek?
In Blade Runner, Harrison Ford's character is tasked with locating and "retiring" genetically engineered humanoids called "replicants" (as in murdering their asses, not setting them up with a nice condo in Palm Beach). Turns out Ford was pretty shit at his job though, because those guys are so ubiquitous they spilled over into other movies.
For starters, remember the "synthetics" in Alien, its sequels, and its pseudo-prequel Prometheus? Well, an Easter egg in the Prometheus Blu-ray Disc implies that those robo-creeps were a sort of continuation to Blade Runner's replicants -- Peter Weyland, the shady, death-obsessed tech millionaire from the Alien franchise, was a friend and mentee to Eldon Tyrell, the shady, death-obsessed tech millionaire from Blade Runner. Ridley Scott, director of both movies, even says he almost called Weyland's company Weyland-Tyrell in Prometheus, which would confirm that the replicants were like the Macs to the synthetics' iPads.
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Neither of which exist in this universe, since people still use MS-DOS.
But, connecting these two movies opens up a whole other universe of possibilities. We already know, for example, that the Alien movies take place in the same reality as the Predator ones -- not just from the regrettable Alien Vs. Predator crossover series, but also from the end of Predator 2, when Danny Glover sees a Xenomorph skull among the Predators' trophies.
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It uses the Xenomorph's tongue jaw as a back scratcher.
So, when replicant Roy Batty said, "I've seen things you people wouldn't believe" at the end of Blade Runner, he may have been referring to two Predators 69-ing or having a three-way with a Vulcan. No, really.
Remember Soldier, the 1998 Kurt Russell space punch-fest no one remembers? Probably not. It's about a bunch of soldiers genetically engineered to be badasses, much like the replicants -- which is no coincidence, since it shares a screenwriter with Blade Runner, and he openly called Soldier a "side-quel" to that film. There are other shout-outs to the Alien-verse in Soldier, but that's not all: A scene detailing past missions of the main character lists "Nibian Moon" and "Antares Maelstrom," which are, of course, places mentioned in Star Trek II: The Wrath Of Khan.