When it comes to courting fan controversy, Emmy Rossum knows the drill. As Christine Daae in the big-screen version of Andrew Lloyd Webber's classic stage musical "The Phantom of the Opera," Rossum had to prove herself worthy to the fans of stage goddess Sarah Brightman, the actress who originated the role in London's West End and on Broadway.

Now, five years after she charmed and disarmed fans and critics of "Phantom," Rossum is back in the hot seat in "Dragonball Evolution," the big-screen adaptation of the Japanese manga, cartoon and video game phenomenon "Dragonball Z."

But unlike her graceful turn as Christine, Rossum -- as the "Dragonball's" female lead, Bulma -- has her dukes up, is locked and loaded, and ready to take the heat.

"Initially there's a shock to hold the burden and feel the responsibility to the character and the fan base," Rossum said in a recent @ The Movies interview. But at some point, she added, you have to let go of those worries and proceed with the character for the project at hand.

"I had seen the cartoon growing up so I knew about Bulma, but when I got the opportunity to audition for the movie I ordered the manga and started brushing up on my 'DBZ' knowledge," Rossum explained. "After I studied the magna as much as possible, I tried to bring the essence of the character to the live-action version. You have to understand that things are going to have to change as you stay as true as you can to the material."

By the way she handles herself as Bulma, you'd never be able to tell that Rossum, 22, was a novice at action moviemaking.

"It was an exciting opportunity to do something I've never done before," said Rossum, who previously starred in "Mystic River," "The Day After Tomorrow" and "Poseidon." "I really respond to material that gets me excited and that's a challenge. Prior to the movie, I had never even seen a gun, rode a motorcycle or been in a comic-book adaptation."

Opening in theaters Friday, "Dragonball Evolution" follows the quest of Goku (Justin Chatwin), a powerful warrior who seeks to recover seven mystical dragonballs to prevent Lord Piccolo (James Marsters) from controlling the universe. Bulma is intent on retrieving the mystical orbs as well, but for her own reasons.

Also starring in "Dragonball Evolution" is Chow Yun-Fat as Master Roshi, who guides Goku on his mission.

Rossum said she was on pins and needles before she met the charismatic "Crouching Tiger, Hidden Dragon" and "Hard-Boiled" star, but the actor soon put all of her worries to rest.

"Working with Chow-Yun Fat was intimidating at first because he is such an iconic action hero. I thought the first time I met him, he was going to come in so ultra-serious, wearing a trench coat with guns blazing like in 'Hard-Boiled,'" said Rossum, laughing. "But he was the most down-to-earth, funny, almost goofiest guy I had ever met. It was so much fun to work with him. He, of course, could do all the fight scenes in his sleep -- way better than I could have with my three weeks of training."

While Rossum's prep time was short, she said that there was not a moment wasted. But getting introduced to the martial arts wasn't her only responsibility -- she had a crash course in weapons training, too.

"There was a lot of physical endurance training that we did, from three to four hours a day," Rossum recalled. "In addition, I went and trained with the Marines to learn how to shoot different guns and weapons. From there they threw me on the back of a motorcycle, dyed my hair blue and said, 'Action.' It was intense."

While Rossum had a blast on "Dragonball Evolution," she looks forward to a workout of her vocal chords again soon. She plans on recording a follow-up to her acclaimed debut album, "Inside Out," and said she's ready to do another movie musical following her smashing turn in "Phantom."

"I'm feeling the itch to do another one real soon," Rossum enthused. "I just love the combination of singing and acting, and walking the fine line between what's real and surreal. So much of moviemaking and entertainment is escapism, and musicals are among the nicest and most uplifting forms of it."

But while Rossum is ready to sing again, don't count on her returning to the opera stage anytime soon. Having performed in 20 operas in six different languages growing up, Rossum is very aware of the level of commitment that's required.

"Opera is a whole different lifestyle," Rossum said. "You need to build the strength and practice on it every day, and although I could focus on it, it's not something that I could give as much time as I need to. It isn't something like movies where you can cut out the lines if you don't do it right. And there's always a 'take 2' if you don't hit the girl in the right spot."

And Rossum knows all about that hit connecting in the right spot, thanks to the flurry of action she experienced on "Dragonball Evolution." The only problem was she wasn't the girl throwing the punch.

"Somebody dusted me in the face one day and I had a fat lip for the next few days. But, you know, with a little makeup, it looks pretty sexy," Rossum beamed.