the bioengineered human Roy Batty confronts his maker, Eldron Tyrell, the head of Tyrell Corporation, a biorobotics company based in the bleak and decrepit city of Los Angeles. The corporation manufactures human “replicants” for slave labor in colonies across the solar system. Batty is one of the best of Tyrell’s products, but he’s not designed to last. He’s come back to Earth, from an off-world colony, to ask for a longer life. But genetic engineering won’t allow it.