Tom Cruise Credits Katie Holmes For 'Rock Of Ages'

When the cast announcements started pouring in for the big-screen adaptation of hit musical "Rock of Ages," we were surprised by how many A-listers director Adam Shankman and company lined up, including Tom Cruise, Alec Baldwin, Russell Brand, Catherine Zeta-Jones, Mary J. Blige, Paul Giamatti and Julianne Hough.

And as it turns out, no one was more shocked to find himself in a movie musical than Cruise himself.

"You're just as surprised as I am," Cruise told while promoting "Mission: Impossible - Ghost Protocol," adding that his wife, Katie Holmes, was the driving force behind his consideration of the role. "Kate kept saying, 'You've got to make a musical.' The dancing of ['Tropic Thunder' character] Les Grossman is inspired because Kate is a dancer, she sings, and she would take us to [dance classes]," he revealed. "[She would say] 'I've got this dance class for the family, come on we've got to do it, we've got hip-hop class, we've got to do it.' "

Cruise went on to say that he put a lot of research into his character Stacee Jaxx and that he is not based on any one person. "I just kind of studied the whole time period and read a lot of books," he said.

While Cruise might still be a little coy about the role, Shankman told us recently that we're going to see a completely different side of the action star in this film. "For Tom, well, I would say he does an insane version of 'Pour Some Sugar on Me,' that every time I show it to people, they're like, 'Can we see that again?' He and Malin Akerman do one of the most outrageous interpretations of 'I Want to Know What Love Is'; I just hope I get it past the ratings board."

Check out everything we've got on "Rock of Ages."

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