Shun and Ruriko are sent north to find out what happened to a missing A.E.G.I.S. cargo plane. The picturesque landscape is the perfect backdrop for romance to bloom, except for the one-eyed Invader monsters lying in wait! However, this isn’t the only discovery they end up making.
A mysterious girl who speaks in tongue of old, and has the ability to summon the “Gate of Snow”, saves them from the outnumbering Invaders. The young girl is alone in this vast wilderness. Only Shun can free her from her secret prison, as she suffers over a history of pain and loss.
Les Gate Keepers sont envoyés localiser un avion d'AEGIS descendu par les envahisseurs. Sur place, ils sont attaqués par l'ennemi, quand soudain, une jeune et très mystérieuse Gate Keeper contrôlant la glace intervient dans la bataille...