A world-premiere stage version of William Peter Blatty's famous horror novel "The Excorcist" is now playing to Aug. 12 at Geffen Playhouse in Los Angeles. Brooke Shields, Richard Chamberlain, David Wilson Barnes, Harry Groener and Emily Yetter star in the intense play about a girl possessed by the devil. Tony Award winner John Doyle (Sweeney Todd) stages the adaptation by John Pielmeier, the playwright whose Agnes of God also dealt with faith and the supernatural. For more information, click here.