AceShowbiz -

Stephen Moyer has joined the cast of horror film "Priest", Variety reported. The actor, who is currently playing vampire Bill Compton in HBO series "True Blood", will portray a mortal character in this vampire film. He is going to be the brother of Priest, the major leading character portrayed by Paul Bettany.

Also joining him in the cast ensemble is Lily Collins. The actress, who recently appeared in The CW drama series "90210", has been taped to portray Priest's kidnapped niece. Beside this upcoming project, Collins stars in Sandra Bullock-starring film "The Blind Side" which is going to hit U.S. theaters on November 20.

Starting his acting career from theater, Stephen Moyer got his first big screen role in 1997's "Prince Valiant" in which he played the title character. He is currently attached to star in "Tribes of October" as the male leading role. Next, he is expected to share screen with his "True Blood" mortal lover, Anna Paquin, in "Open House".

A vampire-western film, "Priest" is based on the comic book miniseries of the same title. The script is written by Cory Goodman while Scott Charles Stewart serves as the director. Beside Paul Bettany, the film is also starring Cam Gigandet, Maggie Q and Karl Urban.

The plot revolves around a warrior priest who disobeys church law by teaming with a young sheriff and a priestess to track down a murderous band of vampires who have kidnapped his niece. The film is said to be premiered in U.S. theaters on August 13, 2010, while the shooting itself is scheduled to be kicked off on August 24.