D.Gray-man 3-in-1 Edition 1 collects volumes 1-3 in omnibus format and features story and art by Hoshino Katsura.

In a fictional 19th century England, Allen Walker is a 15-year-old boy who roams the Earth in search of Innocence. Washed away to unknown parts of the world after The Great Flood, Innocence is the mysterious substance used to create weapons that obliterate demons known as akuma.

A born exorcist, Walker's primary anti-akuma weapon is the cross that's embossed on his red, disfigured left hand, which contains Innocence. But not only does Walker destroy akuma, he sees the akuma hiding inside a person's soul! Together with his fellow exorcists fighting under the command of the Black Order, Walker leads the battle against the Millennium Earl, the evil being out to destroy mankind.

D.Gray-man 3-in-1 Edition 2 collects volumes 4-6 in omnibus format and features story and art by Katsura Hoshino.

Allen questions whether he is willing to fight the Clan of Noah - after all, he signed up to kill akuma, not humans! With his left eye injured, he can no longer tell akuma from humans, making him a target for attack. Despite this weakness, he is sent by the Black Ministry to find and protect his master, General Cross.

D.Gray-man 3-in-1 Edition 3 collects volumes 7-9 and features story and art by Katsura Hoshino.

Allen has had his heart pierced and his Innocence pulverized by an assassin from the Clan of Noah. Allen is taken to the Asian branch of the Black Order to heal. He is keen to rejoin the battle, but he will not be able to fight again until he learns how to activate his Innocence and turn it into a weapon.