Where the anime ends, and where the books carry onAnime, manga, light novels and web novels, lined up by story arc

Arc Almanac

21 Oct 2026Draft. Not yet checked against the books.

All series / A Certain Magical Index / Arc 12

Arc 12 of 66 in A Certain Magical Index

Arc 12: Deep Blood

In the story: 8–9 Aug

Arc name chosen by Arc Almanac, because the books don’t name it.

I’ve watched through

Seen by the end of Index I.

Railgun stops before this arc.

Seen by the end of Index II.

Seen by the end of The Miracle of Endymion.

Earlier in story order than the end of Railgun S.

Seen by the end of Index III.

Earlier in story order than the end of Accelerator.

Earlier in story order than the end of Railgun T.

Item (episodes 1–2; airing) stops before this arc.

What happens

Touma and Stiyl investigate a school occupied by an alchemist. A girl whose unusual ability attracts vampires stands at the center of the situation, tying the immediate danger to the wider history of Index and her pursuers.

Where it sits

Deep Blood in A Certain Magical Index
FormatVolumesUnitsLanguage
Light novel — A Certain Magical IndexVol 2Prologue–epilogueJapanese
Light novel — A Certain Magical IndexVol 2Prologue–epilogueEnglish
Manga — A Certain Magical Index—CutJapanese
Manga — A Certain Magical Index—CutEnglish
Anime — A Certain Magical IndexIndex ISeason 1, episodes 7–9—

Draft. Not yet checked against the books. Report a wrong mapping.