In a future where most of the earth is submerged or ravaged by earthquakes, the enigmatic being known as Orphan stands at the heart of chaos. Orphan, potentially linked to the world's disasters, seeks to unearth a ship concealed beneath the sea, a calamitous act that threatens to wipe out humanity, sparing only Orphan's devoted followers. Piloting the formidable Grand Cheres mecha, Orphan's agents scour the globe for massive disks that sporadically descend from the sky, wreaking havoc upon impact. When a near-fatal disk incident occurs, Hime encounters the birth of Brain Powerd, a unique kind of mecha distinct from Grand Cheres. Bonding with this sentient machine, Hime assumes the role of its pilot and aligns with an international coalition determined to thwart Orphan's cataclysmic plans and safeguard humanity from impending doom.