Touma Kamijou's life is one of perpetual misfortune, which is why no one is more surprised by his sudden stroke of luck than Touma himself! Having won a trip for two to Venice, the City of Water, Touma and Index are excited for a European excursion. But the Italian peninsula is the home of the Roman Orthodox Church, and when old friends and foes alike show up, Touma's hopes for a relaxing getaway might just get washed away!

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!

Seven days have passed since the start of the Daihasei Festival, one of the biggest events of Academy City. Everyone is participating--Seiri Fukiyose is helping coordinate the games, Komoe Tsukuyomi dresses for the part as she cheers for her students, and of course, famous Mikoto Misaka is blowing away the competition. Even Kamijou has appearances! But a shadow has fallen across the celebrations: The Croce di Pietro. This magical artifact threatens the livelihoods of everyone Kamijou holds dear so he dashes off to try and bring Academy City back from the brink. But Oriana Thompson, the magician known as Route Disturb, and the Roman Catholic Church are determined to bring the bastion of science to its knees. Kamijou is going to need all the help he can get-and some luck for once wouldn't hurt!

Academy City's peacekeeping forces are absent due to the Avignon invasion. In that now lawless land, shadowy groups start moving behind the scenes.--Those acting for their own interests.--Those who love the dark and revel in killing.--Those trying to destroy others' hope.--Those standing up in defiance for those important to them.--Those bringing the battle to the higher echelons.--Those quelling rebellious elements.--Those who would stop a rampage with violence.In this city, which controls all of science, who will survive?

Item’s battle comes to a head as their hideout is raided, and the team reaches its breaking point. Disgusted with Mugino’s disregard for the other members’ lives, Hamazura finds the resolve to stand up to her. Mugino may be a Level Five, one of the strongest espers in Academy City, but she’ll see that even a powerless Level Zero like Hamazura can put up a fight when his back is against the wall!

RISE AND GRIND! ​Desperate to protect those close to her, Zena approaches Satou with a simple wish: She wants to become stronger. Naturally, Satou agrees to help, and he and his party subject her to training so rigorous the other explorers can hardly believe her growth. Not one to be left behind, however, Karina enrolls herself in their Labyrinth boot camp as well! But they’ll need to be quick about it. Satou is due in the royal capital, and if his luck is anything to go by, it’s only a matter of time before trouble rears its ugly head!

In London, the women's dorm in a magicians' base get wild, while in the underbelly of Academy City, Accelerator stumbles upon someone who has been waiting for him all this time.