Say the word ‘exorcism’ and the first thing that comes to mind is the twisty-headed pea soup spewing young girl in the 1973 film based on the book by William Peter Blatty. Thankfully, there’s little of that in Scott Derrickson’s “The Exorcism of Emily Rose,” perhaps to the disappointment of those expecting to see an all-out gore-fest.

The film is a courtroom drama based on true events surrounding the death of a young German girl believed to have died as a result of an exorcism back in 1976. Prosecution (played by Campbell Scott) is convinced Emily (Jennifer Carpenter) died as a result of negligence on the priest’s part, while the defense (Laura Linney) is bent on keeping Father Moore (Tom Wilkinson) off the witness stand and out of jail.

It’s not to say that the film isn’t hair raising, though. In stark contrast to the coolly intellectual courtroom scenes are accounts of Emily’s possession, that even in flashback are deeply disturbing and nightmarish. Derrickson uses the horror relatively sparingly to good effect, resisting the urge to splatter the screen with gruesome detail.

The plot starts out as an argument over whether Emily’s condition was the result of mental illness or true possession. Scott gives a solid, if underused, performance as the God-fearing yet skeptical prosecutor Ethan Thomas, who, despite the fact that his opponent Erin Bruner (Linney) is the protagonist, still manages to sway the viewer into seeing things from his end.

Halfway through the film the story detaches itself from that track, as the agnostic Bruner begins to to have certain experiences that may or may not prove that the possession itself is real. There may be those that might not like that switch-up in the plot, as it pulls the rug out from under the initial controversy, especially with the sort of hokey crucifix-turning-upside-down effect that seems to accompany every exorcism in the movies. Still, the questions remain: how do you convince an intellectual court of law that the devil of religion and superstition exists? Is it better to medically treat a patient against her will or to exorcise her with her consent? Was Emily a country bumpkin who fell victim to circumstance or a victim soul who consented to the torture for higher reasons? It’s worth watching how Derrickson paints himself into that corner. Rated PG-13.

COURTESY PHOTO

Caption: Emily (Jennifer Carpenter) is on her way to meet the Virgin Mary in “The Exorcism of Emily Rose.”