In the face of unbearable loss, the desire to bring back the departed is exploited by the mysterious Millennium Earl. By using the souls of the deceased to power his mechanical weapons called 'Akuma,' he ensnares them for eternity. The only salvation lies in the Anti-Akuma weapon, 'Innocence,' which can free these tormented souls from their metallic prisons. Following three years under General Cross's tutelage, Allen Walker transitions to the Black Order, a coalition dedicated to combating Akuma and the Millennium Earl. Endowed with an arm embodying Innocence and a cursed eye that perceives the trapped souls within Akuma, Allen and his fellow Exorcists must thwart the Millennium Earl's apocalyptic scheme, a plan that threatens global devastation.