Kevin Costner had a run of great success as an actor with a series of intriguing, witty, unselfconscious performances in the late 1980s, beginning with "The Untouchables" and "No Way Out" in 1987, then with "Bull Durham" in 1988 and "Field of Dreams" in 1989. He played a kind of warm, unpretentious, witty, latter-day James Stewart, in roles that showed him off as us, you and me, writ large.

And then, in 1990, he seems to have gone over to the Dark Side, which is when he began to take himself more seriously. It started with "Dances with Wolves," which still showed a certain modesty; but since then, perhaps in the grip of some kind of Hollywood Darth Vader, he has given us "Waterworld," "The Postman," and now "Open Range." All three films were directed by him, and all show a disastrous insistence on pounding us with the obvious. Here's an example from the new film: Costner and Robert Duvall, open range cowboys in the year 1882, are talking near their camp wagon. "Boss," says Costner, "How long we been riding together?"

"Coming up on ten years," says Duvall.

"You know what they call that?" says Costner. "They call that a decade."

No kidding; they do. "Open Range" is a western stuffed to overflowing with every trope of the genre and not an original thought in its head. Our heroes have two sidekicks, one of whom is brutally murdered early on by the thugs who work for evil rancher Michael Gambon, who also has the local marshal in his pocket. The other, a Mexican orphan boy 16 years old, hovers, as we say, between life and death for the duration of the film, until - oh, I can't say this - yes, I can - he drags himself out of bed at the climactic gunfight to shoot the man who - oh, let it go.