Many years ago, certain individuals were bestowed divine abilities to engage in battle with the malevolent Akuma residing in the darkness. These Akuma, under the leadership of the Millenium Earl, seek to eliminate the fragments of "Innocence," the sole weapons that can harm the Earl and his followers and prompt another disastrous flood like the one that unfolded centuries ago. As such, the Black Order surfaced to obstruct the Earl's endeavors. This team of heroes enlists Exorcists, who possess the rare aptitude to manipulate Innocence and fight against the Akuma menace. In the tardy 1800s, Allen Walker, a youngster with white hair and a left arm that transmogrifies into Innocence, as well as a cursed eye that discerns Akuma, joins the Black Order. Accompanied by his comrades such as the capricious Yuu Kanda, the gracious Lenalee Lee, and the cryptic yet jocund Lavi, Allen sets out on a critical mission: to rescue the souls of the Akuma and avert the Earl from destroying the planet.