Youji, Kei, Kelly, and the little bear-shaped robot Oscar are small heroes who must save the town. Today is Youjis birthday, but this doesnt seem to excite him. Whether or not they know this, Kei, Kelly, and the woman who raised him as her own, Anna, seem to be planning something. And thats when it appears over the city – an out-of-control sightseeing airship!