In the far future, a soldier named Leon is torn away from his family on a fabricated charge and sent on a mission nobody is meant to survive. He and his teammates must recover a dangerous weapon from the land that was called Japan two hundred years earlier, now overrun by enormous mutated monsters warped by radiation. Almost nothing is known about their target except its name: Tsugumi. The result is a science fiction action adventure set in a lethal, ruined world.