| Ivan Isaacs|
|Featured in|| Graphic novel|
|Portrayed by||Paul Bettany|
Priest (or Ivan Isaacs in the graphic novel from which the movie is very loosely based.) is the protagonist of both the movie Priest and the graphic novel. As a faithful follower of God, and being highly skilled in combat, he decides to hunt down the vampires who kidnapped his niece, Lucy. However, in order to do this, he has to break the vows he made to give up vampire hunting. He joined the church after the last Vampire war and the Veteran Warrior Priest is living in one of the Church's cities.
The director Scott Stewart explained on MTV's splashpage, "The priests of our story are like Jedi knights. They have these supernatural abilities to fight vampires and they saved humanity before the movie even begins. Now, a generation later, society has moved on from war, and the priests are like pariahs. They're almost like Vietnam vets—they've been cast aside by society and they're now reviled and feared."
In the graphic novel, Ivan was in an orphanage most of his youth, until Mr. Isaacs adopted him so he could serve as a companion for his daughter, Gena Isaacs, after her mother died. Over time, Ivan and Gena become very close. A bit too close to Mr. Isaacs taste, as he sends Ivan to a boarding school, where he decides to become a Priest.
After having written an essay, he comes to the attention of a special branch of the Roman Catholic Church, who then ask him to recover a special artifact named the Domas Porada, a prison which contains Temozarela, and Belial, who sealed himself in there in a battle with Temozarela.
After recovering the artifact, one of the researches of Domas Porada, Piestro, suddenly killed the entire research crew after revealing his true goal: to open Domas Porada, to release Temozarela. Temozarela, realising that Ivan could break him out of the prison, tells Piestro to sacrifice Gena. This causes Ivan to go into a stupor and attempt to open the Domas Porada from insanity. After this, Temozarela manages to escape from his chains, beginning a fight with Belial.
After Belial fights and loses to Temozarela, he goes to Ivan, who realizes what he has done and agrees to give half of his soul to Belial in exchange for revenge. Later, he seems to forget this and simply returns to the mansion. After Belial confronts him and tells him the truth, Ivan slaughters a group of zombies raised by an unknown figure, including Gena.
Ivan now stalks the west as an undead creature sustained solely by his infinite rage. When not using his strengths, he uses weaponry to take out anything that stands in his way.
Ivan then goes on a quest to destroy the thirteen angels.