It's the year 2098 in Megatown, a sprawling city populated by Bios and Cybers. The Bios use the Cybers as slaves; the males work in factories, and the females serve. A young man named Stan Gonzo unexpectedly receives a will from his father, whom he never met. Stan inherits a large fortune and becomes the leader of Kanary, the largest Cyber technology company. There is one big problem, however: Stan's father hasn't died of natural causes. A police officer is sent to investigate the murder, and Stan decides to help him. He must get to the bottom of the mystery, find out who his father really was and who has murdered him, and discover secrets that will change the relationship between Bios and Cybers forever.
Zero Zone is a puzzle-solving adventure with pre-rendered backgrounds representing locations. The player navigates Stan from a first-person view with a point-and-click interface. The camera can be rotated in 360 degrees; however, movement is still restricted by "jumping" from one pre-rendered image to another. Conversations with other characters, gathering clues, and solving puzzles advances the game's story.