Replicants

A replicant is a fictional bioengineered or biorobotic android in the 1982 film Blade Runner and its upcoming sequel Blade Runner 2049. The Nexus series of replicants are virtually identical to an adult human, but have superior strength, agility, and variable intelligence depending on the model. Because of their similarity to humans, a replicant can only be detected by means of the fictional Voight-Kampff test, in which emotional responses are provoked; replicants' responses differ from humans' responses. Nexus 6 replicants also have a safety mechanism, namely a four-year lifespan, to prevent them from developing empathic cognition and therefore immunity to a Voight-Kampff machine. A derogatory term for a replicant is "skin-job."

Philip K. Dick's novel Do Androids Dream of Electric Sheep?, the inspiration for Blade Runner, used the term android (or "andy"), but director Ridley Scott wanted a new term that did not have preconceptions. As David Peoples was rewriting the screenplay he consulted his daughter, who was involved in microbiology and biochemistry. She suggested the term "replicating", the biological process of a cell making a copy of itself. From that, one of them (each would later recall it was the other) came up with replicant and it was inserted into Hampton Fancher's screenplay.

Replicants became illegal on Earth after a bloody off-world mutiny by Nexus 6 replicants, before the events of the film. Two weeks before the starting point of the film, six Nexus 6 replicants escaped the off-world colonies, killing 23 people and taking a shuttle to Earth; the film focuses on the pursuit of the replicants by Deckard, a special police officer called a "blade runner", who investigates, tests, and "retires" (kills) replicants found on Earth.

Nexus 6 replicants had been designed to copy humans in every way except for their emotions. The Tyrell Corporation "began to recognize in them strange obsession", and in order to be able to control them better, started to implant false memories into the replicants in order to give them the years of experiences that humans take for granted; these memories created "a cushion or pillow for their emotions".

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