Based in Los Angeles, Tyrell is named for its founder Dr. Eldon Tyrell and is a bio-tech corporation which produces life-like androids called replicants. Tyrell's slogan is "More human than human." The corporate headquarters is over 700-stories tall. The Nexus-6 replicants are so human-like that the only way L.A.P.D Blade Runner Units can identify them is to perform an empathy test called the "Voight-Kampff Scale."
Replicants are exported to off-world colonies for work deemed too dangerous and degrading for humans such as military operations, high risk industrial work, and prostitution. Six replicants return to Earth seeking to extend their four year life spans. When their leader Roy Batty confronts Tyrell in his private chambers, he demands from Tyrell a life-extending DNA strand. Tyrell says this is impossible due to replicants being entirely organic life forms.