Within the first five seconds of the musical number that opens the film adaptation of "Chicago," director Rob Marshall has established such a sublimely vivacious speakeasy atmosphere of hot jazz, cigarette smoke and showgirls that you'll feel as if you've been transported backstage at a posh 1920s cabaret.

The scene crackles with seductive energy as vaudeville siren Velma Kelly (Catherine Zeta-Jones) prowls across the footlights with a phalanx of sexy dancers, cooing "All That Jazz" in a voice that turns the men at the darkened tables around the stage into putty.

And just for a second, wannabe song-and-dance girl Roxie Hart (Renée Zellweger) imagines herself up there in Velma's place. As the beautiful flapper floozy stands in the shadows at the back of the theater, wide-eyed but reeking of wily ambition, Marshall (who directed the recent stage revival of "Cabaret") shows us a flash of Roxie's imagination in which she's the fabulous star of the fabulous show, wearing a fabulously silver sequined waterfall dress, strutting and singing to wild applause.

So vivid is the unmistakably cinematic experience this film creates -- the exhilarating music, the personality-popping performances, the gorgeous cinematography and brilliantly creative precision editing which distinguish the movie from its stage inspiration -- that within the first five minutes of "Chicago" I knew I was seeing the best movie of 2002.

And it only gets better.

Reality, fantasy and stage performance bleed into one another as the luminary Velma is arrested after catching her cheating husband and her co-star sister together and killing them. Simultaneously, Roxie naively sleeps with a con man who said he'd help her showbiz career, then commits her own murder when he cruelly tells her what he really thinks of her meager talents and slaps her down to the floor when she won't let him walk out the door.

Soon both women are in jail, competing with all their showbiz acumen and feminine wiles for the attention of Billy Flynn (Richard Gere) -- the expensive, unbeatable, headline-grabbing celebrity lawyer who has taken both their cases but seems interested only in whichever one can be manipulated to generate the most publicity.

Adapted for the screen by Oscar-winner Bill Condon ("Gods & Monsters"), whose innovative alterations take full advantage of the cinematic medium, "Chicago" is a movie in which absolutely everything went right.

Zeta-Jones, who starred in West End musicals before heading for Hollywood, is a show-stopper as Velma, the vain, bob-haired vixen who is eventually reduced to proposing a post-trial stage partnership to the now more-famous Roxie (thanks to Billy Flynn). In the surreal plane of Roxie's imagination, Velma's breathless prison-bound audition number begins with a piano player's introduction that goes, "Ladies and Gentlemen, Miss Velma Kelly in an act of Desperation!"

Gere, who has always been adept at playing sleazy lawyers, acquits himself admirably in his musical numbers, especially in the irresistibly punchy "We Both Reached for the Gun," in which courthouse press conferences give way to Roxie's vision of herself as Flynn's ventriloquism dummy and the press corps as his marionettes.

Queen Latifah plays prison matron Mama Morton as a voluptuous, wisecracking homage to Mae West, and puggish sad sack John C. Reilly gives one of the best performances of his career as Roxie's dope of a put-upon husband who is heartbreaking in his solo number, "Mr. Cellophane," in which he laments being invisible to the world in the glare of Roxie's tabloid celebrity.

But it's Zellweger's incredible presence as the ditzy, peroxide blonde Roxie that sucks you into "Chicago," with her kisser lipsticked into a heart shape, her frizzy fingerwave hair and her sultry, charcoal-shadowed doll eyes that encompass with complete credibility everything from nescience to ruthless calculation -- sometimes all at once.

This actress is in the midst of an amazing and sustained blossoming, seeming to become more and more talented with each performance. From "Jerry Maguire" to "Nurse Betty" to "Bridget Jones's Diary" to "White Oleander" the complexity of her characters and her ability to rivet the audience have grown subtly but exponentially. In this film, she's so vivid and dynamic you can almost feel her breath on your face in her close-ups as she belts out Roxie's egocentric numbers with panache coming from of every pore of her body.

Clever and funny, zestfully paced and edited ingeniously to bring the worlds of reality and fantasy together, every moment of "Chicago" is brilliant, all the way to the closing-credits curtain call that gives all the dancers their due.

I'm very picky about my musicals. I'm too much of a literalist to enjoy them unless they really wow me. But this one did, and went straight to the top of my small list of favorites. "Chicago" is, quite simply, one of the two or three best movie musicals I've ever seen.