Megazone 23 III (1989)

Years after the events of Megazone 23 II, the only city on Earth is the supposedly idyllic Eden. There lives Eiji Takanaka, a B Level hacker who has just been accepted into EX, the organization that controls Eden. However, before his first day on the job, he becomes embroiled in a network war, a legendary figure named EVE, and a plot to re-inhabit the Earth.