When Earth was devastated by humanity's greed and carelessness, the human race left their planet on gigantic space-faring cities called Megazones. Only Megazone 23 survived to return to the regenerating Earth, and now the remnants of humanity live sealed up in the city of Eden, awaiting the SYSTEM's decision that humanity is responsible enough to be let out and repopulate the rest of the planet. Ruled over by the SYSEM, most of Eden's inhabitants live in security, except for a small group of renegades called netjackers, who appear intent only on causing chaos.
The story focusses on Eiji Takanaka, an ex-hacker turned hotshot computer games player, who has just got a job in E.X, the group that serves the SYSTEM. But Eiji begins to discover disturbing things, things that affect the fate of Eden itself. Who will Eiji side with in the upcoming conflict for control of Eden? Who is the mysterious Sion? Is the virtual idol Eve just a computer generated entertainment, or is she a real person? This is one hell of a ride!