Touma Kamijou just can't catch a break. He might live in Academy City, a place full of more super powered students than you can shake a stick at, but his only superpower is his supernatural lack of luck. He wants nothing more than to keep a low profile, but when a girl named Index comes into his life, it gets more complicated and dangerous than ever!

Mikoto Misaka is a Level Five esper--one of the most powerful in Academy City. She's so powerful, in fact, that her DNA has been harvested to create a series of clones--the "Sisters." But who is behind these clones, and why would they go to such lengths? The sinister truth is nothing she or Touma could have imagined, and it involves the terrifying Accelerator, the most powerful esper of all time!

Summer vacation is over, and it's time to go back to school! The new school year brings a new friend for Index--the lovely, thoughtful Hyouka Kazakiri. But there's a new problem too, and it's tall, blond, and ready to ruin Touma's day--the terrifying magician Sherry Cromwell!

A certain unlikely hero...Only Komoe's class would let a regular conversation spiral out of control into a grand-scale hot pot party. It's an open question whether her students are a blessing or a curse. Meanwhile in London, the English Puritan Church's facilities should generally be a place of prayer and quiet contemplation...So who's going to take responsibility for the chaos unfolding in the sisters' dorms?! Back in Academy City, a certain railgun's mother has suddenly popped in for a visit, which is more than enough to make even a Level Five esper panic!

A certain unlikely hero...No one was able to stop Second Princess Carissa's plot in time, so the worst has come to pass: London has fallen. The city of magic, home to the English Puritan Church and Index, now rests in the hands of the Knight faction. Soldiers control nearly every critical part of the country, commandeering the very streets of the capital. Still, the Puritan sorcerers haven't given up the fight just yet!As the battle for the UK rages on, Touma heads to Folkestone to save Index-only to run straight into the coup d'état's mastermind herself! Worse, Acqua is still alive, and his holy sword, Ascalon, is pointing not at Touma but at Carissa!

A certain unlikely hero... Ever since the attack on Academy City, the disputes between the magic side and the science side have been getting worse day by day. Now protests have broken out in France, instigated by a sinister magical artifact, and world tensions are nearing their breaking point. Unable to just stand and watch, Touma Kamijou flies off to Avignon in order to use his trump card, Imagine Breaker, but he should be a little more wary of what could be waiting for him in the historic stronghold of the papacy...

A certain unlikely hero... Touma Kamijou has the worst luck imaginable... Sure he's a citizen of Academy City, a scientific marvel of the modern world where superhuman abilities are artificially cultivated and commonplace, but when it comes to paranormal talent, Kamijou's been classified a Level Zero-a loser, basically. Oh, he does have one trick up his sleeve (literally), but even that's more trouble than it's worth. When Kamijou encounters a delusional young girl convinced she's a nun and raving about being chased by evil sorcerers, he's eager to send her on her way and get back to failing his studies. Fate, it would seem though, has other ideas, and he suddenly finds himself caught up in a supernatural intrigue with a girl named "Index" at the center! Science and magic collide in this first volume of one of the most popular light novel series ever penned!