Cop Land.

When a melodrama really works, no one, not even a critic, sits around grousing about its lack of psychology, sociology, or sentiment. Who would trade the delicious rot of Chinatown for an in-depth study of incest? Or insist that the noose-tightening power of In the Line of Fire is worth less than the windy speculations of Oliver Stone's JFK? Good melodrama has a poetry of its own.

But when a melodrama doesn't quite work, yet has something of value in it, there may seem to be another movie, a better movie, perhaps even a non-melodramatic movie looming up behind (and rebuking) the film you're watching. Such is the case with Cop Land.

James Mangold's script has an irresistible set-up. Some cops, sickened by their New York City beats, have settled their families into a tranquil New Jersey town. In fact, they are the town; practically everyone in sight is a cop or the spouse or child of one. Back and forth each workday these men go into or out of New York, but even when twilight finds them in their cosy ranch houses or in their for-cops-only bars, they've still got the city racketing in their skulls. Fights break out over beers and the cops go home to beat their wives (who are often sleeping with other cops).

The sheriff of this town, Freddy Heflin (Sylvester Stallone), may be a law officer but he knows he's not a real cop. Cops bust criminals; Freddy hands out speeding tickets to tourists on their way to the Big Apple. Unable to join the N.Y.P.D. because of partial deafness, he drinks with cops, tries to break up their fights, sees the girl he's always pined for (the very she for whom he sacrificed his hearing while rescuing her) marry a cop, and witnesses small-town delinquencies, marital problems, feuds. No matter how rowdily the off-duty cops behave, Freddy regards them as heroes; no matter how tolerable they find Freddy, they can't think of him as anything other than a big boy at best, at worst a lumbering clown.

Writer-director Mangold does his own evocative material intermittent justice. There are some clever strokes, such as the way a big-time cover-up in the big city is paralleled by Freddy's two-bit concealment of his own drunk driving. And the acting is generally good, though a spectacular trio of actresses - Janeane Garafalo, Cathy Moriarty, Annabella Sciorra - can do no more than fill out sketchy roles. Sylvester Stallone's Second Coming turns out to be...not bad at all. Paunched up and more sad-eyed than ever, he is sufficiently pathetic slumped against a bar and, for some heroics in the last reel, he's only as heroic as Freddy would be - no Ramboesque invulnerability but just a good man driven to his limits. But the best performance by far is Harvey Keitel's as the unofficial mayor of the town. No one plays an-ulcer-waiting-to-happen better than Keitel. All the resentment of underappreciated, underpaid cops and sensation-hungry press, seems to be coagulating somewhere between Keitel's hunched shoulders as he stares down at his beer glass and snarls at his chums. A limited but powerful player, Keitel has spent half his career playing angry lawmen. This performance is the actor's ne plus ultra.

But it takes more than effective acting and slick direction to produce a first-rate movie. A good filmmaker knows where the heart of his material is, and I'm not sure that Mangold does. He has invented a big conspiracy to energize his story, but I think it's the wrong sort of energy. Freddy discovers not only that some cops have come up with the money for their homes by winking at big-city drug dealing but they've also concealed the whereabouts of a young patrolman whose shooting of some criminals could be interpreted as vigilantism. The latter crime is supposed to uncover the former but there's no real connection between the two, and the fugitive cop could have been easily cleared merely by examining his bullet-ridden tires and finding a certain shotgun. Mangold is so eager to turn his movie into High Noon that he cynically manipulates his own story. Just when Freddy is about to cooperate with Internal Affairs, the case is shut down by New York's mayor, who has been suborned by drug kingpins. (Take that, Giuliani!) So only by taking matters into his own hands can Freddy achieve justice. And this one-man-strike is connived at by the frustrated Internal Affairs investigator. Had the gentleman never heard of the New York Times and the time-honored American traditions of whistle-blowing and news leaks?

Implausibility leads to implausibility. At several points in the action, it would benefit the corrupt cops to murder Freddy, but these villains, who don't hesitate to murder their fellow officers to conceal evidence, are perfectly content to warn the sheriff off. Why such restraint from such desperadoes? Again, it's dramatic cynicism, and it keeps Mangold from pursuing the deeper implications of his own story. And what would those be?

At the conclusion of this movie we are meant to believe that the town has been morally cleansed because a few corrupt cops are gone while all the rest - honest men and true - can live in peace. But about those honest men? Surely the real, bleak vision of Cop Land resides precisely with those honest cops who are kept entirely off screen. Do not honest policemen occasionally have to use violence in the performance of their duties? And cannot just force sometimes corrode as surely as the unjust use of it? In Cop Land all the adulterers, wife-beaters, and barroom brawlers also seem to be in on the drug conspiracy that Freddy explodes. But suppose they weren't? Don't some honest cops beat their wives? And couldn't honest cops, even in the bucolic bliss of some small New Jersey town, find that violence and corruption have infiltrated their hearts, disrupted their peace, shattered their families? This is the substance of the great, phantom, unmade Cop Land hovering behind the fatally flawed, though fairly entertaining Cop Land now playing.