The ninth arc of A Certain Magical Index, consisting of volumes 9 and 10 of the light novels, and episodes 8-13 of the anime's second season.
An interpretation of this arc from Mikoto's viewpoint can be found in the A Certain Scientific Railgun manga, but unlike the Sisters Arc, deals with its own story separate from Touma's.
- A Day in the Limelight: For Fukiyose Seiri, Stiyl, and Motoharu.
- Arc Villain: Lidvia Lorenzetti and Oriana Thompson.
- Chekhov's Gun: The night parade Miss Komoe mentions to Himegami ends up being what prevents the Croce di Pietro from activating, as the fireworks block the starlight the ritual needs.