D.Gray-Man is set in a fictional 19th century and follows Allen Walker, a young exorcist charged with the destruction of 'akuma', creatures created with a mechanical body and a human soul, which prey on mankind under the orders of the Millennium Earl. As an exorcist, Allen is compatible with 'Innocence' which gives him an anti-akuma weapon, in this case, his deformed left hand, which allows him to kill akuma.
In the first volume, Allen is searching for the headquarters of the 'Dark Religious Organisation', the group of exorcists who fight the Millennium Earl, under the instructions of his teacher, also a member of the Organisation. Along the way, he encounters an Akuma which is killing people in a church and a young boy who has started his own akuma patrol.
I had heard promising things about this manga from friends who had read it in Japanese, and it doesn't disappoint. In many ways, it reminds me of Fullmetal Alchemist, and so far the plot seems quite gripping. The Millennium Earl is a rather creepy and disturbing villain while the akuma are both scary and rather pitiful. Allen makes a cute hero, and seems quite innocent. The art is lovely, neither too plain or too ornate, with nice details. I did find some of the plot quite scary, especially the akuma bullets which transmit a virus which quickly kills living things, and the akuma themselves are draw to look very unnerving.
Overall, so far, D.Gray-Man seems to have a good plot and interesting characters. I'd definately recommend it to people looking for a new manga series to follow.