在学园都市制作的宇宙升降机“恩底弥翁”完成在即的某一天，上条当麻和茵蒂克丝与一位无能力者（Lv0）少女鸣护艾丽莎相遇了。 茵蒂克丝与艾丽莎两人因为“旺盛的食欲”这样谜一般的羁绊而意气相合起来，就在三人享受放学后的愉快时光之时，带着魔术师的史提尔突然发动了袭击。而本次袭击的目标正是艾丽莎。为何身为科学世界的艾丽莎会被魔法世界的人追击？因为受到了魔法世界的强烈攻势，学园都市一侧的莎特奥拉率领着秩序维护部队开始了行动。 上条与茵蒂克丝还有艾丽莎他们因被卷入这样的状况而极度混乱迷茫，史提尔对他们这样说道：“那里的她，将会引发魔法世界跟科学世界之间的战争。” 在科学与魔术魔法交汇之时，以“恩底弥翁”为舞台的故事开始了！
![とある科学の超電磁砲[レールガン]S 大事なことはぜんぶ銭湯に教わった](https://image.tmdb.org/t/p/w342/k240qywPWpJK4LKDjI4e8Rj3697.jpg)
After rescuing Last Order and subsequently taking a bullet to the head, Academy City’s top-ranked esper rests in the hospital. But Accelerator’s recovery is cut short when a mysterious girl carrying a photo of his little clone companion asks for help. Now they’re taking on Disciplinary Action—an anti-evil coalition whose sinister plans threaten Last Order, Academy City, and even the entire world!
Kamijo is a student in Academy City, where people use science to develop supernatural abilities. The guy’s got a lot of heart – luckily for a young nun named Index. She’s on the run from a sorcery society that covets the astonishing 103,000 volumes of magical knowledge stored in her memory. When Index stumbles into Kamijo’s life, she finds a faithful friend and protector, and while Kamijo’s easily the weakest kid in Academy City, he’s got something else going for him: the Imagine Breaker, an unexplainable power stored in his right hand that negates the powers of others. With scientists and sorcerers attacking from all sides, the Imagine Breaker will definitely come in handy – but it’s Kamijo’s loyalty to Index that will be his greatest weapon in the fight to keep her safe.
Misaka’s electro-manipulation abilities – and delightfully destructive Railgun projectile move – make her a rock star in Academy City. The techno-metropolis is packed with supernaturally powered students known as espers, including Misaka’s flirty friend and roommate, Kuroko. She uses her teleportation skills as a member of the Judgment law enforcement team, fighting crime alongside her fellow agent Uiharu. Joined by their friend Saten, a spunky Level 0 esper, Misaka, Kuroko, and Uiharu have a blast taking on danger whenever and wherever it arises.
