The America of 1968, laments the Harlem crime boss Bumpy Johnson (Clarence Williams III) to his protégé Frank Lucas (Denzel Washington) in “American Gangster,” “has gotten so big you can’t find your way.” One might argue that expectations surrounding Ridley Scott’s new film have swelled to equally contentious proportions.

“American Gangster” is the highly anticipated first salvo in this year’s Christmas season assault on the ticket-buying public. It has also been the butt of extended movie business gossip surrounding seven years of costly attempts to bring the film to the screen, a revolving door of directors who have included Brian De Palma, Antoine Fuqua, and Terry George, and last week’s Internet posting of a pristine digitized pirated version of Mr. Scott’s finished film. If there’s one thing that mainstream Hollywood film-going teaches, it’s that diminished expectations are the key to a positive movie-going experience. Yet with “American Gangster” out in the open and on the big screen at last, it’s a pleasure to report that the wait has been well worth it and that the film will likely satisfy almost any viewer’s hope of getting his money’s worth at the multiplex.

Though the title suggests a monolithic single-person character study, as adapted from journalist Mark Jacobson’s New York magazine article, “The Return of Superfly,” by A-list screenwriter Steven Zaillian, “American Gangster” is actually the true-life story of two middle-aged men minting success out of failure and harnessing the wisdom with which they’ve been blessed by those who have gone before them. When Bumpy Johnson dies, his former driver, Frank Lucas, decides to run the Harlem rackets his own way. Mindful of Bumpy’s observation that the various players in New York’s highly competitive illegal narcotics trade are “pushing out all the middlemen,” Lucas sets his sights locally, but extends his reach globally. Through a GI cousin-in-law who has become the owner of a Bangkok club, Lucas establishes business ties directly with Asian heroin producers and pays off U.S. Army transport personnel to deliver his goods stateside.

The resulting flood of very pure and very cheap heroin so decisively undercuts Lucas’s competition that even mafia don Dominic Cattano (Armand Assante) is forced to eat crow and accept Lucas’s terms. Cordoned behind an executive wall made up of his brothers, cousins, and nephews, it would appear that so long as Frank’s kin remain loyal, the Vietnam War keeps the planes flying between Southeast Asia and America, and his identity remains unknown to the good cops who would jail him and the bad cops who would bleed him dry, he is set for life.

Essex County police detective and night-school law student Richie Roberts (Russell Crowe), meanwhile, has made a shambles of his own life. Dishonest at home and overworked on the job, Richie’s workaholism and womanizing have cost him his marriage. Too honest for his own good at work, he has become a pariah within the department. But when his partner falls prey to both Richie’s do-goodism and the new high-octane heroin that lately has nearly the whole city strung out, Richie embarks on his own mid-life crusade. Recruited by a fledgling federal task force, he sets out to uncover who is behind “Blue Magic,” the brand name that is making corpses out of junkies, junkies out of dabblers, and lavishing riches on the mysterious uptown dealer behind it all.

The problem with Mr. Washington’s uncanny on-screen depth, charisma, and resonance is that the actor’s embarrassment of interpretive riches tends to highlight any haphazard scripting, hackwork direction, and amateurish performing on the part of his collaborators. In “Training Day,” for instance, Mr. Washington sometimes seemed to be in a truer, better-shot, and better-written movie than the rest of the cast. Mr. Zaillian’s script for “American Gangster” expertly and nearly seamlessly condenses roughly five years of incidents into a story that is so satisfyingly crafted at a character level that the necessary splicing, combining, and fabricating of history have no negative impact on the experience of the film. In lesser hands, the fact that young Frank Lucas witnessed a KKK lynch mob murder his cousin would have spawned a literal-minded flashback depicting young Frank’s gruesome introduction to the racist ways of the world. But instead of being forcefed that information on-screen, we see not what the lynching looked and sounded like, but what it meant to Frank in a flash of recognition across his face as he recalls it decades after the fact. Throughout “American Gangster,” Mr. Washington demonstrates that an emotionally articulate actor is the filmmaker’s most potent storytelling tool.

Mr. Crowe, who, truth be told, shares much less screen time with Mr. Washington than the film’s advertising suggests, charts a smart and interpretive course through “American Gangster,” roughly halfway between his paradigmatic roles as the inarticulate whistleblower Jeffrey Wigand in “The Insider” and the two-fisted badge bully Bud White in “L.A. Confidential.” When Detective Roberts does at last come face to face with his quarry, their scenes have an amiable and straightforward quality that is the polar opposite of the teeth-gnashing confrontations with which most latter-day cops-and-robbers epics inevitably climax. Like virtually everyone else in the appropriately sprawling cast of “American Gangster,” Mr. Crowe’s performance complements Mr. Washington’s, and vice versa.

In the past, Mr. Scott, the revered director of “Alien,” “Blade Runner,” and “Blackhawk Down,” has often taken the high-budget directorial low road by stitching together polished and impersonal visual conceits that in films like “G.I. Jane,” “Gladiator,” and “Hannibal” appear to be cribbed from the big-budget TV commercials for which he is equally renowned. Mercifully, in “American Gangster,” Mr. Scott exhibits remarkable directorial discipline and self-control. The film, shot by “Zodiac” cameraman Harris Savides in an irresistibly ugly, washed-out patina that will be familiar to anyone with photo album snapshots dating back to the 1960s, establishes and sustains a coherent pace that ennobles and respects its characters and its audience with equal generosity.

As familiar as all the belted leather coats, afro hairdos, sideburns, big cars, and pop music beats in “American Gangster” may seem, the need, rage, and loss beneath the film’s seductive retro sheen are its strongest assets and rare rewards, indeed, when gambling nearly three hours of one’s life that a Hollywood blockbuster will yield well-crafted, passionate, and worthwhile entertainment.