DK.
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Here's the official synopsis for Priest, which hits theaters on May 13, 2011.
PRIEST, a post-apocalyptic sci-fi thriller, is set in an alternate world -- one ravaged by centuries of war between man and vampires. The story revolves around a legendary Warrior Priest (Paul Bettany) from the last Vampire War who now lives in obscurity among the other downtrodden human inhabitants in walled-in dystopian cities ruled by the Church. When his niece (Lily Collins) is abducted by a murderous pack of vampires, Priest breaks his sacred vows to venture out on a quest to find her before they turn her into one of them. He is joined on his crusade by his niece's boyfriend (Cam Gigandet), a trigger-fingered young wasteland sheriff, and a former Warrior Priestess (Maggie Q) who possesses otherworldly fighting skills.
The studio describes the concept thusly...
10,000 days ago Comet 23 struck the Pacific Ocean with the magnitude of all the nuclear weapons in the world. A lucky few survived the heat blast and fire storms. And then the freezing began. The comet knocked Earth away from the sun; encasing the planet in snow and ice. For those who survived, life was violent and dangerous. The daily battle wasn’t just against the punishing climate but against each other for the basic necessities that meant life or death. Still, the weather was growing colder and the ice was expanding. Then they found an object from the past, buried deep in the ice. And with it came a choice. A choice that could either save them or destroy them.
Check out the trailer.