03/11/2009 at 10:00 AM EDT
knows how to work a red carpet – but even an Oscar-winner can get rusty.
Roberts, who stars with Clive Owen in Duplicity
, was taken aback by the size and enthusiasm of the crowd gathered for the film's London premiere on Tuesday.
Asked how it felt to be on the red carpet after being a mostly stay-at-home mom for awhile, she said, "Just terrifying, awful. It's scary out there – but it's nice."
She even admits feeling nervous about her fashion choices. "I've put on three different outfits to come here tonight, three!"
Roberts, who last year starred in Charlie Wilson's War
, says being back in the spotlight isn't what she craves. "I don't have the bug to work, I have the bug to make good movies and those don't come along very often," she said.
For Roberts Duplicity
was tempting enough to bring her back to the big screen – but it took a bit of coaxing from her costar Clive Owen. "I [took] her out for lunch and told her that I'd read a script that was dynamite and it would be great for the two of us to do it," said Owen at the premiere. "She was actually pregnant, so I had to wait another year before she finally read it and said yes."
As for how Roberts handles balancing her career and her family life with husband Danny Moder, 3-year-old twins Hazel and Phinnaeus and 1-year-old son, Henry, "[It's] surprisingly easy," she said. "Good kids, good support, great husband."
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