An epic struggle—not between God and Satan, but between a socially relevant courtroom drama and a 70s-style demonic exploitation movie. An ambitious attorney (Laura Linney) agrees to defend a Catholic priest (Tom Wilkinson) charged with negligent homicide after a young woman from a pious farm family dies during an exorcism. It all seems to be happening in the present, somewhere in the American heartland, though the woman on whom the story is based, Anneliese Michel, died in 1976 in Bavaria (the religious hysteria that led to her death was stoked partly by the German release of William Friedkin’s The Exorcist). The script is a lifeless succession of moral debates and stormy horror flashbacks, though I had a good time watching Jennifer Carpenter, a comic Buffy type in White Chicks and D.E.B.S., hurl herself around as the title character. PG-13, 118 min.