D.Gray-man season 4

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.

The season initially ran from October 2, 2007 to September 30, 2008, on TV Tokyo in Japan. Thirteen DVD compilations of the second season, each containing four episodes were released by Aniplex between March 5, 2008 and March 4, 2009. In June 2016, the series was licensed by Funimation for an English-language release in North America. In August 2017, Funimation announced they would release the series' second half on home media version starting on October of the same year.

Three pieces of theme music are used for the series: one opening theme and two ending themes. The opening theme is Uverworld's "Gekidō" (激動). The two closing themes Mai Hoshimura's "Regret" for episodes 77 to 89, and Stephanie's "Changin'" for the rest of the season.