D.Gray-man Hallow is a sequel to the original D.Gray-man anime series that follows Allen Walker, an exorcist of the Black Order who wields a cursed weapon known as "Innocence" to fight against the Millennium Earl and his demonic army of Akuma. The story follows Allen's journey to save mankind from the Earl's evil plans. In this season, Allen and the other Exorcists are faced with a new enemy, the Noah Clan, who possess immense power and seek to destroy the world. With the help of his friends and allies, Allen must battle against the Noah Clan and protect the world from their sinister ambitions.