In a post-apocalyptic future, Neutral City has sprung up on ruins located between the militant nation of Ragna and the sentient forest that controls the area's water supply. While on an adventure one day young Agito, whose father helped found the town, falls into some deep ruins. There he discovers a stasis structure that still contains one perfectly-preserved living person: a girl named Toola, who comes from the civilization prior to the calamity that destroyed the Moon and ravaged the Earth. Accidentally awakening her, Agito helps Toola adjust to this very different new world, but she has trouble accepting it and is swayed by Colonel Shanuck of Ragna, a man who, like her, awakened from stasis a few years earlier, and seeks a device that could undo the damage done to the world – and Toola is, of course, the key to finding and activating it. But activating Istok could just as well be the doom of the world as its salvation, and that is something the forest will not allow.