Priest takes place in a kind of alternate universe. In this world, man and vampire have been at war for centuries. During the opening credits, we see battles between man and vampire dating back to what look like the crusades. At some point, the church created priests. The priests are warriors who are the only ones who can fight vampires. The priests in this movie are similar to jedi knights.
The movie begins after the last great vampire war. For protection, humans live in walled cities (except for a few people who for no reason live out in the wilderness). Most of the vampires have been killed. The ones who still live were rounded up and put into reservations. Since the church thinks vampires are no longer a threat, they have disbanded the priests. They are now pariahs of society. They are kind of like vietnam vets in the way they are treated.
The movie is set in a post apocalyptic future. The city looks like something out of Blade Runner or Highlander 2.
Paul Bettany plays a priest. His brother is one of those crazy people who choose to live on a farm outside the protection of the city walls. One day his home is attacked by vampires. He and his wife are killed (or nearly killed) and the daughter, Lucy, is kidnapped. The local sherrif asks Bettany to go find her and rescue her.
The movie is partially a remake of The Searchers. Swap vampires for Comanche and the vampire war with the civil war. He even takes the young, inexperienced sherrif along, and they argue about whether they will have to kill Lucy. The sherrif even pulls a gun on the priest, but at least he doesn't say "I hope you die!"
There is nothing in Priest to recommend. No humor, the vampires aren't scary (CGI is just not scary), and the action scenes are not good. You can skip this movie.