If Stephen King wrote more books like "Different Seasons," his name probably wouldn't be so reviled by movie critics.

The four-story collection has already spawned two fine movies, 1986's "Stand By Me" and the even-better 1994 drama "The Shawshank Redemption." And now a third story from the book has inspired the new film "Apt Pupil." And if the results aren't quite as good as the other two, it's certainly head and shoulders above most King adaptations.

That's due in no small part to British character actor Ian McKellen, whose chilling portrayal of a fugitive Nazi war criminal propels this psychological horror movie over some really rough spots.

Also, it should be noted that the film lacks a moral center and remains rather ambiguous on certain aspects of the subject matter, which tends to trivialize what millions of real-life Holocaust victims went through.

McKellen stars as Kurt Dussander, an elderly recluse living in a small suburb of Los Angeles. His idyllic lifestyle is upended when a nosy teenager, Todd Bowden (Brad Renfro), discovers his horrible secret: Kurt is actually Arthur Denker, a former SS officer who served in several concentration camps.

Using the man's fingerprints and other evidence of his identity for leverage, the teen blackmails Denker into sharing some of his terrifying war memories, including the atrocities he committed in the death camp. Their cat-and-mouse game of psychological terrors eventually spills out into Todd's life, threatening to destroy his relationships with others and his spotless school record.

Although they seem to have built a tentative and very uneasy friendship, there's a definite air of distrust between the two, which worsens when Denker turns the tables on the boy. The man claims to have documented their conversations and meetings and threatens to implicate the boy if his secret is revealed.

Besides McKellen's riveting and creepily mesmerizing performance, the film also benefits from effective direction by Bryan Singer ("The Usual Suspects"), who lets the tension build very slowly throughout the first hour.

That's not to slight the rest of the cast, which is quite good. Renfro's transformation from a naive teen to a cornered animal is very believable, while David Schwimmer is surprisingly well-cast as Todd's clueless guidance counselor.

"Apt Pupil" is rated R for profanity, a violent stabbing and other brutal attacks, gore, use of vulgar slang and a vulgar gesture, male nudity, brief simulated sex and simulated marijuana use.