With its stunning cityscapes and Chanel-ad surreality, "Someone to Watch Over Me" shows off director Ridley Scott's extraordinary visual artistry. The sets are so sumptuous, you'll want to move right in. But the haze is so thick, you'll need to bring a defogger. Scott, who directed "Alien" and "Blade Runner," looks at the world through veils of smog. What with these pictorial pollutants, he loses sight of plot.

"Someone" suffers somewhat from Scott's blind spot, but it's still a reasonably enjoyable romantic thriller with "Platoon's" Tom Berenger on his best behavior. Berenger plays a happily married cop who becomes sexually involved with a homicide witness from the Upper East Side. It's not a fatal attraction, mind you, but certainly there are parallels. The message in both movies: Don't take your love to town.

Berenger, like Robert De Niro, looks altogether different from movie to movie. Here, he's the beefy but attractive detective Mike Keegan -- more like Rocky than the Tom Selleck clone he played in "The Big Chill" or the Vietnam villain Sergeant Barnes. Making "dees" of these and "dose" of those, he sounds like a commoner from Queens.

Mimi Rogers (Mrs. Tom Cruise) and newcomer Lorraine Bracco have the supporting roles as, respectively, the socialite Claire and the loving wife Ellie. There's a compelling chemistry between Berenger and the brunettes, with Rogers' chilly elegance set against Bracco's blue-collar bravura. Both actresses give sympathetic performances, but Bracco eclipses both costars. The former cover girl and disc jockey bites down on the part of Ellie Keegan like a good-tempered pit bull. Ellie, a cop's daughter, a crack shot and a devoted wife, knows a derringer from a Berenger.

Scott obviously enjoys this sort of heroine. On the other hand, he has a tendency to treat Rogers as scenery, much as he did Sean Young in "Blade Runner."

Claire, imperiously vulnerable, sees her oldest friend murdered at a chichi Manhattan hot spot and is then menaced by the killer. Joey Venza (Tony DiBenedetto), a hit man who becomes a psycho, pops out now and again to scare her, clearly a contrivance created to keep Mike and Claire in close proximity until they become smitten by their biculturality.

The affair commences: The devoted Ellie cleans the windows while Mike escorts Claire to charity benefits. She is charmed by his blunt manner and folk wisdom. "These people are a bunch of screaming squirrels," he says of her friends. And then there is the old standby, "You are some beautiful woman." (Very common, almost always works.) To his great credit, Berenger makes that line believable.

"Someone" has its moments, but this vehicle is running on fumes. Actually, a lesser director might have handled this modest proposal better, might have made less of a production of what is a rather plain action drama. Scott is a grand impresario, and this is just one of those things.

Someone to Watch Over Me, at area theaters, is rated R. It contains profanity, violence and sexual situations.