Note: There are several versions of Blade Runner.
In Los Angeles, November 2019, Rick Deckard (Harrison Ford) a retired police officer, is arrested at a noodle bar by officer Gaff (Edward James Olmos). His former supervisor, Bryant (M. Emmet Walsh), tells him that several “replicants”, biologically engineered humanoids that serve as soldiers and slaves in colonies on other planets, have escaped and come to Earth illegally. As a “blade runner” while active, Deckard’s job was to track down replicants on Earth and “retire” them.
Bryant shows him a video of another blade runner (Morgan Paull), administering a Voight-Kampff test, which distinguishes humans from replicants based on their empathic response to questions. The subject of the test, Leon (Brion James), shoots the tester when it is likely he will be exposed as a replicant.