Beyoncé Knowles takes time off from her musical career to bring the thinly disguised story of the Supremes to the big screen in Dreamgirls.

NEW YORK—The list of famed singers who have tried their hand at acting is lengthy. It is also an eclectic group, one that ranges from Eminem to Barbra Streisand and from Elvis Pres ­l ­ ­ey to Diana Ross. However, most singers have been drawn to films that include musical performance. Beyoncé Knowles decided to make her acting debut in a movie in which she did not sing, Austin Powers in Goldmember, and she recently costarred with Steve Martin in The Pink Panther. She has more than made up for this with a role in Dreamgirls, a film based on the hit Broadway musical of the 1980s. (The film opens in Vancouver on Christmas Day.)

In a New York hotel interview room, Knowles says that when she heard that the musical was about to be adapted to film, she went out of her way to be a part of it. “My choreographer, who I have been working with since I was 15, had been telling me about the play forever. It has this cult following and he has seen it a hundred times, and when he told me that it was going to be a film, I said, ”˜I have to be a part of it no matter what I have to do, even if I am only on-screen for five minutes, because it will be a classic film.’”

The film, like the play, is a thinly disguised biography of the Supremes, the 1960s singing group that featured Diana Ross as lead singer. Knowles plays Deena, an impoverished young woman who thinks that a trio called the Dreams will be her best shot at getting out of Detroit’s ghetto. She is one of two backups to the lead singer, Effie (Jennifer Hudson), who has a powerful voice and stage presence. The group loses a local talent contest but gains a manager, a local car dealer named Curtis Taylor Jr. (Jamie Foxx), who feels that Effie is the group’s greatest asset. He becomes her boyfriend and mentor. However, when it comes time to record and tour, he concludes that the group can be bigger with the pretty Deena in front and Effie as a backup. Although the change brings internal dissension, it appears to be the right business move when the group becomes internationally famous.

When Knowles first contacted the film’s director, Bill Condon, she was aware that despite her success as a member of another famed trio, Destiny’s Child, she would probably need to audition for a role in the movie. She says she invited Condon to Destiny’s Child rehearsals and says that after he had seen the group, she was worried she might have scared him off.

“I am more like Tina Turner on the stage than I am like Deena,” she says. “My vocal performance and my dancing are nothing like Deena’s, and he said, ”˜You are going to have to do a screen test,’ because he wasn’t sure if it would be believable to an audience, particularly when I was ”˜young Deena’ and really plain. I knew that if he didn’t believe me as Deena, there was no way I was going to get hired to play [the less attractive] Effie. I knew that Deena was not the biggest part, but I didn’t care. When I went off to do the screen test, I found the ugliest dress and the ugliest wig and put these big eyebrows on.

“So they found their Deena. I blocked off six months of my schedule and cancelled the tour I had planned. I did it for a quarter of the money I make, the money I can make for one show, but I didn’t care about that. I didn’t want to perform or do anything outside of the Dreamgirls work. I had shrines built to Diana Ross in my trailer. I lost 20 pounds and I did whatever I could to get the part right, including rehearsing on the weekends. It was a part that was very different for me from anything I had done before, but I wanted to get it right. I am from a singing group, and if it wasn’t for groups like the Supremes, I wouldn’t have international tours and be on the radio in Germany. This tells that story and it shows that there is a price to be paid for fame. There is something sad and empty about fame, and this reveals part of that side.”

Knowles isn’t living that life. Although Destiny’s Child still does some work together, her solo career is going well. And her personal life isn’t too bad either. She is in a relationship with rapper–media mogul Jay-Z, who owns the New Jersey Nets basketball team on the side. (Reports recently had her spending as much as $3 million on a birthday party for him.) She says that although Deena is crushed when her group loses the singing contest, her own experience losing on the network show Star Search was not as deflating. She says she’s very supportive of shows like American Idol, which gave her costar Hudson, a contestant in 2004, the exposure she needed to get the part in the movie.

“Deena is different from me because she grew up in the projects and she didn’t have a father and she wasn’t a strong singer, whereas I have both of my parents and I am in control of my life and I sing lead because of my voice. And when we [Destiny’s Child] lost on Star Search, I still had a nice house and was going to a private school, whereas Deena had to sneak back into bed because she wasn’t even supposed to be out that night. After Star Search, I had my mother and father and best friends, and we could perform in things, and then someone saw us and we got an opportunity. That is why I think it is great that in these little towns they have American Idol tryouts so that if people really want to make it, they get a chance. I think it is incredible that Jennifer could go from being unknown to being on the show and then having an opportunity like this. I can only imagine the pressure she had doing this film, because she’s never done a movie or an album and yet she has the biggest song in the movie, the one that gets the applause in the theatre [“I Am Changing”], so that’s a lot of pressure. In fact, when I told people that I was playing Deena, the first thing they said was, ”˜Who is Effie and can she sing it [“I Am Changing”] and does she get it right?’”

There have been rumours that even though Knowles had signed on to play Deena, which is a supporting role on-stage, she was adamant that the studio (DreamWorks) promote her as the lead and Hudson as supporting actress for awards. (The Hollywood Foreign Press gave a Golden Globe nomination to Knowles for best actress in a musical or comedy and nominated Hudson for best supporting actress.)

Knowles says that she was never jealous of Hudson because she knew she was a bigger star going into the film and had nothing to prove. “I didn’t do the movie to become a big star,” she says. “I am already a big star, and the thought of being bigger is scary. I knew that I would have to hold back vocally, and in the beginning I would have to be the oddball with the eyebrows. But that was part of the character, and I am comfortable with that because I don’t have anything to prove at this point as far as being a singer and a star are concerned. I already have nine Grammys. I am already a big star, so this was all about the acting for me.”