"Requiem" is a difficult to categorize film about possession that does not completely fit into any single genre. It will probably disappoint many hard-core horror fans and please lovers of hard-hitting dramas and mysteries.

The film showed at 2006 Chicago International Film Festival, and it will be opening in Chicago on November 17.

The film is based on the same basic incident that inspired "The Exorcism of Emily Rose," the story of Anneliese Michel, a 23-year old German student who died in 1976 after a painful exorcism. "Requiem" discards most of the violence, special effects and supernatural elements, which dominated the other film.

Michaela is a seemingly decent, sensible adolescent who is demure and deeply religious. She gets along well with her patient father, but she continually clashes with her strict, puritanical and parochial mom. It can be argued that the main character’s apparent possession is just a psychological reaction against her mom’s dominance.

With her dad’s help, Michaela arranges to go away to college but they keep it a secret from her mom. When her mom finds out, she feels betrayed and expresses serious reservations about the daughter leaving. We later find out that the mother was right.

Michaela starts well at school and she quickly falls for a fellow student named Stefan. He breaks off the relationship and ends up with her only close female friend, Hanna. After this Michaela has a full-fledged breakdown. She has epileptic fits and she acts like she is possessed by a hostile spirit.

Michaela goes to a priest who thinks she is possessed by a demon, but others think her problems are all psychological or psychosomatic. I still was not sure myself what I thought at the end of the film, but the movie’s ambiguity actually enhanced it.

"Requiem" is not especially frightening, and it has a disappointing ending. But the rich, psychologically complex lead performance by newcomer Sandra Huller helps to raise it above most of the other films about possession.