"This is the moment where Deena finally finds her voice," she explains. "The whole movie she's been manipulated and she's kind of lost her own opinions. I think a lot of women can relate to the lyrics."

"The shoes were absolutely killing me," she says. "I'm 5'2". Miss Jennifer is 5'9." Beyoncé is 5'6." So in order for me to be seen in the picture with the two of them … I had on some heels that were at least 4 inches, and in the finale, 5 inches. I was ready to cut my feet off and give them away!"

In Dreamgirls, Eddie Murphy plays James "Thunder" Early, a character who's part James Brown, part Little Richard, and all Eddie Murphy. As a fan of the musical, he was excited to be cast in the film. "I'm much older than the rest of the cast," he says. "I saw the original play on Broadway 25 years ago and I loved [it]. I was blown away when they asked me to be in it."

Like the rest of the cast, Eddie does all his own singing in the film, but even he admits that the pop albums he put out in the '80s weren't a good example of what he could do. "I don't know if 'Party All the Time' gave you any [idea] of what was coming—that this was coming 20 years later," he jokes.

Former American Idol contestant Jennifer Hudson beat out 782 other hopefuls to make her film debut as Effie White in Dreamgirls—and according to Oprah, it isn't just a breakthrough, she crashes through the wall! "I think it's a religious experience listening to her sing," Oprah says. "She makes the little hairs on the back of your neck stand up."

Jennifer says that all the attention she's receiving feels like a blessing. "It's God's favor," she says. After auditioning three times in six months, Jennifer felt the decision was in the hands of a higher power. "I ended up on the church steps across the street from my house and I said, 'Lord, here I am. If it's meant for me, it's for me. Whatever your will is, that's what's best for me, and that's what I want,'" she says. "Two weeks later, they called me saying, 'Congratulations, Jennifer Hudson, you're Effie White.'"