A silent cataclysm befalls Japan: a celestial entity of unimaginable scale, a single monstrous eye as vast as the archipelago itself, now hangs in the sky. Its unblinking gaze plunges the nation into paralysis and despair, with no explanation from science or government. As society teeters on the brink of collapse, a second miracle occurs. From the skies, the streets, and the seas, an army of one trillion magical girls materializes, forming an impenetrable, living shield around Japan. While the world watches in awe, only a solitary young woman named Hikari knows the truth behind their summoning—a secret that holds the key to humanity's salvation or its ultimate end.