Tom Hulce could make Mozart into an 18th-century Bruce Springsteen and no one would be the wiser, but if Jamie Foxx didn't sound and move exactly like Ray Charles, his failure would be evident for all the world to see.

It's the major pitfall of playing a contemporary figure, and one that's made even more difficult when the figure you're portraying actually shows up to watch your performance.

Luckily, the cast of "Notorious," an upcoming biopic about the late Biggie Smalls, comes through with flying colors, insisted Sean Combs, who is portrayed in the film alongside other hip-hop artists like Lil' Kim, Tupac Shakur and, of course, the Notorious B.I.G.

"It's rare that you get a movie made about you when you're still relevant, but [they] took on the challenge," Combs said of the cast, adding that he was especially impressed with actor Derek Luke, who is playing Diddy. "People asked me years ago who you'd want to play me, and I said Derek Luke ... so it was just destined. I got to see him do his thing, and it was scary for me. I had to leave, 'cause he was acting just like me."

But while he had high praise for Luke, Combs saved his greatest enthusiasm for Jamal "Gravy" Woolard, a young rapper cast as one of the greatest MCs of all time.

"Gravy, the guy playing B.I.G., it was just too eerie for me to be on that," Combs marveled. "Gravy's killing it. If I tell you he's killing it, then that's all we need to say, you know what I'm saying? I don't think anybody could have done a better job."

"It's a little creepy," echoed the flick's music supervisor, Deric "D-Dot" Angelettie. "You know he's not B.I.G., and we accepted that, [but all of] B.I.G.'s people ... looked to Gravy and said, 'You can play B.I.G. You could do it!' I believe that Gravy has studied hard enough; I think he got enough battle scars from the streets that he could pull it off. We're very happy that he's a part of it."

Angelettie revealed that, as music consultant, he's been working with the actors to "make sure they sound like B.I.G. and [his widow] Faith [Evans] and Kim," he said. "To make sure the beats are right, the soundtrack is going to be right."

But as much as the film is about music, about the story of one man's journey from Brooklyn to the penthouse, it's more about Biggie's mother, Combs asserted. Voletta Wallace, who lives in the New Jersey house her son owned, will be played in the film by Oscar nominee Angela Bassett.

"It's not my movie," Combs said. "A lot of people don't know this, but it's not my movie. It's Miss Wallace's movie. It's from a mother's perspective. I'm just there as support."

"It's good for his mom. It gives [her] some relief that the world really appreciated her son. It's good for Brooklyn, it's good for hip-hop," Angelettie added. "It's [gonna be] very good."

"Notorious" will open in January.

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