IN THE entrancing "Crash," Terrence Howard and rap singer Ludacris are characters on two sides of the socioeconomic fence. Howard plays a milquetoast, bourgeois television producer, and Ludacris is a desperate young man who has resorted to carjacking. A life-threatening circumstance draws them together, and they come to a certain bracing appreciation for each other's humanity.

A similar and yet vastly different situation draws these two actors together again, in Craig Brewer's rather wonderful "Hustle & Flow." This time, Howard's the have-not, a pimp who wants to make the music big time, and Ludacris is the have, a narcissistic rap star (if that's not redundant) who doesn't give the little people from his home town the time of day. Once again, things get highly charged: A gun forces them to reassess each other.

But despite its hip-hop trappings and a little handgun action, "Hustle & Flow" isn't about the rage and bigotry that suffuses "Crash." It's more of an urban fairy tale, a surprisingly charming story that -- in certain sections -- almost crystallizes into the sweetness of a Mickey Rooney-Judy Garland musical. And the other crucial difference is this: In "Crash," Howard was a bit player in an ensemble drama. Here, in "Hustle & Flow," he compels you like a master hypnotist. Every nuance of that tentative character you saw in "Crash" is effectively rubbed out. As DJay, a Memphis boy who decides to make a difference in his sorry, nowhere life, Howard owns every upstroke and downstroke of this movie.

DJay has been making a living in the shadows, pimping his bottle-blonde hooker Nola (Taryn Manning) to low-rent customers. It's an ugly existence for everyone: himself, Nola, his other prostitutes, including Shug (Taraji P. Henson), and the truck-riding customers. The dominant feeling in this sub-universe is degradation, financial misery and spiritual ferment. But DJay takes his "job" seriously. He has to turn a profit and keep the women happy. In a sense, he's running a family. But this life is heading nowhere, slow.

When he bumps into an old friend, Key (Anthony Anderson), a music sound engineer, DJay starts thinking about a dream he let slide: to do something with his gift for words. He starts writing out some spoken poetry, his "flow." And he begins to imagine it being set to music. Key turns him onto Shelby (DJ Qualls), a white, scrawny but savvy musician with a beat machine who has a passion for hip-hop and can lay down a fat groove.

"You know he white, right?" DJay mutters to Key, looking askance at Shelby's pale, pale skin.

"Naw, he ain't white," Key says. "He light-skinned."

Little by little, a song called "Whup That Trick" takes foot-stomping shape. It's time to record a demo tape. DJay has always talked a big game about how he knows Skinny Black (Ludacris), the local boy who became a successful hip-hop musician. He intends to slap that tape into Skinny's hand and get the break he's always dreamed of. And when the women get fussy because DJay's wiggy departure into music is cutting into their income, DJay thinks of ways to involve them, too. And that's where the Judy-Mickey business comes in, as Key sets up an impromptu studio, lining his walls with egg cartons for acoustic absorption. These guys are building their version of the Rooney-Garland barn to put on a show. Sure, the folks involved are a twangy accented pimp and a small squad of geeks and hookers. But the magic is exactly the same.

If this story convention evokes a certain -- shall we say? -- whiff of Camembert, it's only passingly so. "Hustle & Flow," which won the Audience Award at this year's Sundance Film Festival, is about something finer: the primary conviction of these characters, who have dared to step from poverty to dream state. They're so real and vulnerable you can feel the collective ache. And none aches with more resonance than DJay, whose eyes slowly flood with tears when he hears a gospel singer in church -- the first stirring of his dream deferred -- and then with increasing triumph, as that quest promises to become real.

But this is also the real world, and, sooner or later, DJay's going to have to face Skinny Black, whose self-absorption is almost impregnable. That's going to be where the rubber of DJay's aspirations meets the road.

Writer-director Brewer, who also made 2000's "The Poor and Hungry," doesn't go light on the obscenity, which is part and parcel of the language of the characters. But that puts earthy conviction behind the storybook elements. The grittiness and softness need each other in an intriguing yin-yang of hip-hop and Hollywood hokum. He has blended everything so beautifully that no one should be surprised if America's suburbs soon ring with people of all ages chanting, "It's hard out here for a pimp."

HUSTLE & FLOW (R, 114 minutes) -- Contains sexual scenes, drug content, pervasive obscenity and violence. Area theaters.

Terrence Howard, right, with Taryn Manning, gives a strong performance as a pimp turned rapper in "Hustle & Flow."Prostitute Shug (Taraji P. Henson) and musician Shelby (DJ Qualls) in "Hustle & Flow," a vividly compelling drama by Craig Brewer.