09/28/2007 AT 06:00 AM EDT
Rumer Willis liked the wig she's been wearing in her latest movie so much that she had her hair dyed platinum blonde for real.
Showing off the 'do at Thursday's opening of the James Perse store in Beverly Hills, the 19-year-old daughter of Demi Moore
and Bruce Willis
and stepdad Ashton Kutcher
told PEOPLE that her new look jolted her folks, as well as her siblings, Scout, 16, and Tallulah, 13.
"I came home and my parents were really shocked when I walked in the house," she says. "My sisters looked at me like, 'What? Your hair!' But everyone, my parents, loved it."
That was a relief. The makeover – by Tracey Cunningham at the Neil George Salon in Beverly Hills ("She's amazing", Willis says) – required seven hours to complete. (What do you think of Rumer's new hair color? Weigh in on our StyleWatch blog.
"Honestly, it just took a long time. I got there at like 1 [p.m.], and I didn't leave until 8 p.m. I have really dark hair, so it took a long time, but it didn't really hurt," she says.
"I got the idea because the movie I just finished, I was wearing a blonde wig, so I saw myself like that. And I just went for it."
The movie comedy, I Know What Boys Like
, was previously called House Bunny
Says Willis: "I always find that whenever I'm doing something big in my life, I want to change the hair."
Reporting by AMY KEITHSee more transformations in our StyleWatch photo gallery – and vote on their best looks! Who's turning 40? Which celebs are high school dropouts? What's hot and definitely not in fall fashion?
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