"The Jacket" moves like a thriller yet rarely does anything thrilling. Take out all the obvious marks of thriller-dom -- the tense music, the flashy editing, the frightened looks on people's faces -- and you'd have a decent psychological drama. It's not that it fails as a movie altogether; it's just that it fails to be what it's trying to be.

It begins during the Gulf War of 1991, where Jack Starks (Adrien Brody) is shot in the head and develops retrograde amnesia. Some months later, he is wandering in Vermont, where he accepts a ride from a fellow drifter (albeit a drifter with a car). They are pulled over by a state trooper. Flash ahead one year: Jack has been convicted of killing the trooper and is sentenced to a hospital for the criminally insane. But Jack has no memory of what happened, and he's not insane. So what happened?

The hospital is populated with "One Flew Over the Cuckoo's Nest" characters and has a maverick doctor in its midst. He is Dr. Becker (Kris Kristofferson), scruffy and gravel-voiced, and possessed of some unusual therapy ideas. Jack is taken by Becker and his crew in the middle of the night, strapped into a raggedy patchwork straitjacket, put on a long metal tray and slid into a morgue drawer.

For some reason, when he is in this jacket and locked in this drawer, Jack experiences an alternate reality. He finds himself in 2007 -- 15 years ahead of the present -- encountering a woman named Jackie (Keira Knightley), whom he met just before accepting that ill-fated ride from the drifter. Jackie was a little girl at the time, and now she wonders how it is that Jack, whom she remembers vividly, has not aged in the intervening years. Avoiding the sun and using a good moisturizer can only account for so much.

The sci-fi mysteries of the jacket are not explained, thankfully -- those "explanations" never make sense anyway -- but Jack does begin to see that his actions back in 1992 in the mental hospital might alter or prevent unfortunate events in the future. Like his own death, for example, which he learns is imminent.

My fear is that in describing the film, I have made it sound more interesting than it is. It surely has the potential for excitement -- it deals with time-travel, after all, that old standby -- but it remains somber and slow-moving most of the time. Director John Maybury seems so intent on being artsy that he forgets to have fun, and Massy Tadjedin's screenplay simply wanders listlessly from one plot point to the next.

There is also the matter of Keira Knightley, who, lovely though she may be, is consistently one-note in her portrayal of the depressed and downtrodden Jackie. I wonder if the role is too serious for her as an actress. Her previous characters have mostly been fanciful -- pirate maidens, medieval princesses, that sort of thing -- not grounded in harsh reality like this one.

And I must say, Adrien Brody is beginning to grate. Like "The Pianist," "The Jacket" is another chance for him to be St. Adrien the Martyr, to gaze heavenward with that beatific smile of his, accepting his dreary fate so that others might live. I don't mind a character who is called upon to endure a lot, but if he's going to be so smugly "humble" about it, I just want to smack him. Put on the jacket, see the future, and stop evil-doers, Adrien. That's what this movie needs you to do.

Grade: C

Rated R, some harsh profanity, some violence, a little nudity, some mild sexuality

1 hr., 42 min.