The plot, which takes place at the end of a fictional 19th century Europe, revolves around Allen Walker. Allen is a member of the Black Order, a group of Exorcists connected with the Vatican. Their mission is to stop The Millennium Earl, an evil ghoul planning to cleanse the world by destroying all humans in the manner of Noah's great flood.

The Exorcists themselves are special people gifted with the ability to control and use Innocence, a divine substance created in the ages past to combat the Earl's minions, the Akuma. It is said that there are exactly 109 units of Innocence scattered around the world. Once an Innocence finds its compatible person, it will evolve to become a weapon to fight the Akuma.

As the story progresses, Allen is introduced to more Exorcist characters, among them are Yu Kanda, Lenalee Lee, Lavi, Arystar Krory, and Miranda Lotto. Also in the spotlight are the older brother of Lenalee Lee, Komui Lee, the church's science department supervisor; Bookman, a mysterious colleague within the church; and Cross Marian, a General in the Organization and Allen's master.

More villains also appear along the way. There are higher level Akuma, with greater power, skill, and intelligence. Also appearing is the Clan of Noah, a group of humans descended from Noah himself. Each member is gifted with great power, and the group has allied themselves with the Earl.

Several characters are named after silver jewelry brands. General Cross's golem, Timcanpy, draws its name from Tim Campi Design. The names of Road Kamelot and Tyki Mikk are taken from the "Lord Camelot" and "Tiki Mic" designs.

Type: TV
Episodes: 103
Status: Finished Airing
Aired: Oct 3, 2006 to Sep 30, 2008
Producers: TV Tokyo, Aniplex, Dentsu, TMS Entertainment, FUNimation Entertainment
Genres: Action, Adventure, Comedy, Shounen
Duration: 23 min. per episode
Rating: PG-13 - Teens 13 or older