The fourth season of the D.Gray-man anime series, called the "2nd stage", was directed by Osamu Nabeshima and produced by TMS Entertainment. It adapts Katsura Hoshino's manga. Like the rest of the series, it follows the adventures of Allen Walker, an Exorcist that wields the power of "Innocence" to fight against the Earl of Millennium, an ancient sorcerer seeking to destroy the world with monsters called akuma. In this season, Allen and his allies are trapped in a dimension known as Noah's Ark and must fight the Earl's underlings in order to find a way home.