In the late 19th century, Allen Walker becomes an official member of the Exorcists, an organization dedicated to destroying Akuma, mechanical weapons created by the Millennium Earl using the souls of the dead. Allen possesses a cursed eye and an arm that houses an anti‑Akuma weapon, empowered by the Innocence, a divine gift bestowed upon him as an apostle of God. Together with his fellow Exorcists, Allen must thwart the Millennium Earl's final scheme, which threatens to bring about the destruction of the world and all its inhabitants.