地獄怪客是二次世界大戰期間，德國納粹在一次實驗失敗下，被其中一位科學家所喚醒的恐怖生物，他是死神撒旦的兒子，具有紅色的皮膚、以及長長的尾巴，因為奇怪的外表，所以輾轉被一位美國特務收養。 在地獄怪客成長的過程中，他漸漸地失去原本的邪惡本性，感染到其養父的慈悲胸懷，而變成了一位正義的角色，伴隨著其他也具有特異功能的好友，一起調查駭人聽聞的超自然現象，就在此時，地獄怪客開始接觸到他的過去、以及他如何的來到這個人世間，他將變回天性邪惡的性格？或是從此跟邪惡勢力誓不兩立？

A nine year old boy named Joey, who after the tragic death of his father, begins to experience psychic powers such as allowing him to move inanimate objects with his mind, set things on fire, and even communicate with his dead father. However, not everything is good for Joey as his newly gained powers accidentally awake an evil supernatural force that is contained inside the body of an old ventriloquist's dummy that Joey found in an abandoned house. The supernatural Dummy shows similar powers to Joey's, and soon he puts the lives of everyone near Joey in danger as the evil Dummy has dark plans for Joey's special powers.

學園都市製作的宇宙升降機「安迪米昂」完成在即的某一天，上条當麻和茵蒂克絲與擁有「奇蹟」的歌聲的少女鳴護艾莉紗相遇了，茵蒂克絲與艾莉紗兩人因為「旺盛的食慾」這樣謎一般的羈絆而意氣相合起來，就在三人享受放學後的愉快時光之時，帶著魔術師的史提爾突然發動了襲擊。而本次襲擊的目標正是艾莉紗。為何身為科學世界的艾莉紗會被魔法世界的人追擊？因為受到了魔法世界的強烈攻勢，學園都市一側的莎特奧拉率領著秩序維護部隊開始了行動。上条與茵蒂克絲還有艾莉紗他們因被捲入這樣的狀況而極度混亂迷茫，史提爾對他們這樣說道：「那裡的她，將會引發魔法世界跟科學世界之間的戰爭」。 在科學與魔術魔法交匯之時，以「安迪米昂」為舞台的故事開始展開。

Bonus animation featuring Index-tan included with the BD special edition of the Toaru Majutsu no Index: Endymion no Kiseki movie.

Documentary exploring such phenomena as astral projection, telekinesis, telepathy, voices from beyond the grave, ghosts/spirits, etc.