What could be more ominous than a movie about a black cop and a white cop? All the combinations are worn too smooth to move anymore, from streety-mouth kid Eddie and stinky old Nolte to madcap Mel and wise old Glover. As for the chronic theme of cop realpolitik and consequent corruption, stop it! Bored now! Plus, today's cop movies are lousy with hard-shelled softies who attain grudging racial rapprochement in the heat of the night prowl of gangbangerland. Most cop-movie makers should be turned over to the authorities.

So my hopes were low for Training Day, noted music video director Antoine Fuqua's flick about a Dirty Old Pragmatist, Alonzo (Denzel Washington), showing a Dewy Rookie, Jake (Ethan Hawke), the bloody LAPD ropes. But instantly, Denzel won me over. Nasty in black from his thug cap to his victim-stomper boots, he manages a better evil makeover than I could have imagined.

The odor of sanctity has clung too much to this man. He's forever playing upright symbols in do-good dramas: Biko, Malcolm X, white-coated docs, white-collar lawyers, black righters of wrong. When he's a rebel, it's for a cause: a submarine hero defying a warmonger commander, a Gulf War hero ashamed of his medal, a Civil War hero demanding dignity. His films' titles tell the story: Courage Under Fire, Cry Freedom, Glory. And he's preposterously perfect; when Newsweek needed an actor whose ideal facial symmetry illustrated the science of human beauty, Denzel was their man. He wouldn't boost his career by doing the blockbuster Seven: It seemed "evil" to him. His Oscar might as well have been for Best Moral Actor–in fact, they should make all the Oscar statues in his image. They would seem more purely gold.

So the badder-than-Bad Lieutenant Alonzo is the role Denzel needs as desperately as the genre needs him. And he's better than Harvey Keitel in basically the same part. Harvey's hypocrite narc bellowed his degradation through a megaphone of self-pity; Denzel, armed with a smarter script, plays Alonzo like an insinuating jazz sax, all tricky riffs that hide melody's meaning from the uninitiated. For the longest time, it's hard for us to tell that Alonzo really is wholly evil.

We regard him through the big button eyes of Jake as Alonzo lays down the law in his "office," a low-down Monte Carlo rolling through LA's scarier scenes. "Unlearn everything you learned at the academy; it'll get you killed," snaps Alonzo. So far, so Popeye Doyle. "In order to protect the sheep, you got to go after the wolves. And to catch a wolf, you got to be a wolf." What keeps this from being familiar is Alonzo's skill at keeping Jake, and us, off balance. When you see it written down, you see it's horseshit. But while Alonzo's talking, you're intimidated by his flashpowder temper, seduced by his teasing, inviting grin, mesmerized by his rousing preacher phrasing (Denzel's real-life father was a preacher), manipulated by his ambiguous cackle when you invariably get everything wrong. Jake is also scared of the vision of the future Alonzo shows him: a cop writing parking tickets, or helping a lady with a flat tire. If Jake can't prove he's a wolf in his first twenty-four hours on the job, he won't pass Alonzo's muster, and that's his sole shot at getting ahead.

Ethan, a wispy poet onscreen and off, who can't seem to grow a proper beard at 30, seems an unlikely partner for Denzel. That's why Denzel forced the studio to cast him. The contrast is so extreme, it makes the innocence/cynicism collision seem fresh. Jake, unstreetwisely bookish, terminally earnest, reminds me of my nice, white friend on the National Book Critics Circle who watched Menace II Society and afterward asked a friend, "Hey, how come those two gang guys called each other 'Holmes'? I mean, what are the odds they're both named Holmes?" In scene after relentless scene–staged by inner-city émigré Fuqua without much rhythmic sense overall but with great feeling for lingo, place and pace–Denzel points out to Jake the horrors of the narc cop's beat. The two men are like mahogany and balsa wood; weigh them in a balance and the balance becomes a catapult, with poor Jake soaring, bewildered.

The great thing is, race isn't just a cliché in Training Day. It is a climate of opinion, a toxic haze. When Alonzo shakes down a carful of white college kids who're in the hood to buy pot, threatening to make them walk home, there's real zeal in it, and palpable fear in the kids. When Jake decides he'll knuckle under to whatever test Alonzo devises, Alonzo gloats, "My nigger!" with a contempt that also suggests a perverse admiration. It's practically impossible to convey racial emotions without lapsing into cliché, or ill-informed, overpaid-screenwriter cluelessness, or sincere but poorly dramatized rage. You need a ferocious and delicate touch, and dialogue like music. That's what you get in Training Day.

Thanks to the obbligato of menace, only the very pulpiest and most preposterous parts of the story break the spell of plausibility. It plays so naturally when Alonzo goads Jake into smoking the pot they've seized–"To be truly effective, a good narcotics agent must know and love narcotics!" (Comparable scenes in the 1991 druggie-narc film Rush came off all phony, and that was a nonfiction story. To be truly effective, a good narcotics story must be written more persuasively than real life.) But uh-oh. Jake's point of view from the lurching Monte Carlo turns all absinthe-hued and woozy, and Alonzo gleefully informs Jake that what he just smoked was PCP-laced pot. (When Paul McCartney, urged to puff PCP by Harry Nilsson, inquired if it was fun, Nilsson reflected, then replied, "No.") Alonzo tells Jake not to worry about getting busted: The captain's got their backs, he'll warn them about urine tests a week ahead. "It's not what you know, it's what you can prove!"

It's all fixed, all part of Alonzo's grand plan to topple the kingpins. He takes the greenish Jake on his rounds: He ambiguously bonds with a fine-Scotch-sipping Überdealer (Scott Glenn), roughs up a wheelchair-bound street-level dealer (rapper Snoop Dogg, pretty good) and conducts a larcenous search in the home of a sarcastic, very stoned woman (singer Macy Gray, who's terrific–how ever did she learn to act so convincingly stony?).

When Alonzo pays a visit to the South Central crime neighborhood he rules with feudal impunity, the movie starts to shed some of its hard-won street cred. The street feels right: Fuqua and Denzel actually consulted the locals for dialogue and authenticity tips. And the look of this gangland is refreshingly sinister, not just stylized. But events take a turn for the hackneyed, partly because of the pressure to come up with a conventional studio-movie finale. Alonzo's motives are revealed, reductively. Something about Russian mafia gambling debts. The Russian mafia–that's our new deus ex machina when plotting gets desperate. Forced to get simply wicked, Alonzo sheds the many skins that kept us guessing. There is a remarkably preposterous denouement involving a Catholic schoolgirl saved from rape–no spoiler, you'll see it coming for an LA mile–and a rather too drawn-out shootout, formulaic chase and man-to-man rooftop-hopping smackdown.

But I'm not complaining. At least Training Day offers a reasonably satisfying ending to a coherent story, a task the vast majority of movies no longer even pretend to care about. Denzel finally gets a role that outdoes Don Cheadle, whose funny, scary villain stole Devil in a Blue Dress from him. Ethan gets an arc from liberal wimp to scarred nihilist with a heart of gold; in the end, it proves to be a fair acting fight between him and his great career benefactor. When Jake the worm and his narc-cop master mix it up in a niftily choreographed Mexican-standoff scene, Alonzo eyes him with a newly proud contempt. For an instant, you get the idea that Alonzo really still buys just a bit of his own line of bull–that he was just a gruff drill sergeant, traumatizing the kid for his own good, just to prepare him for this day. Today, a mere cub cop earns his wolf badge.

Denzel could earn an Oscar, but I doubt it. The Academy, more corrupt than Alonzo, is easily scared, especially by black men not driving Daisy or driving home obvious lessons that make Academy members feel good. But no matter. Alonzo appears to be spitting real venom; he's having as much fun as Roy Cohn in Angels in America. Training Day proves we underestimated Denzel Washington in esteeming him; his performance cries freedom and shatters the shackles of niceness. Now, that's glory.