A girl with nothing becomes the flashpoint for a war that should never happen. Kamijou's powerlessness against the machinery of two worlds, magic and science both grinding toward collision, forces him to fight with his fists and his refusal to let Arisa become a tool. The movie trades the TV series' episodic sprawl for a single, escalating nightmare where every decision narrows the path forward instead of opening it.
Academy City stands on the brink of completion for its most ambitious project yet: a massive space elevator called Endymion. But before the grand opening, Kamijou and Index stumble onto Arisa, a seemingly ordinary Level 0 student with no powers. The encounter should be harmless, except magicians descend on the city seeking her, turning streets into battlegrounds and forcing Academy City's elite defenders into action. As the conflict escalates, Kamijou discovers Arisa isn't just a random target. She's the linchpin in a carefully orchestrated plot involving both magic and science, two worlds on the verge of open war. With Stiyl's guidance, they begin piecing together why a powerless girl holds such weight in the balance between these opposing forces. What starts as a rescue mission spirals into something far larger. Kamijou must navigate competing agendas, impossible choices, and the question of whether the impending war can be stopped or only redirected. This story merges high-octane action with the underlying tension between two worlds that were never meant to coexist.