Replicants are human-like androids featured in the 1982 film Blade Runner. The Nexus replicants are nearly identical to humans but have great strength and agility. They are impossible to differentiate from humans without a lengthy one-on-one Voight-Kampff test, which measures emotional responses. Replicants can display emotions but do not actually feel emotions. They also have only a four-year life span, an effort to deprive them of the ability to develop feelings. Replicants who rebel from their manufactured purpose are slated for “retirement,” a euphemism for killing. Blade Runner features Harrison Ford as Rick Deckard, a police officer/bounty hunter tracking down some rogue replicants. It is arguably one of the best science-fiction movies ever filmed.