NEW YORK (AP) — Before she was Princess Anna in "Frozen" or even Veronica Mars, Kristen Bell was a musical theater geek. Now she's letting her roots show.

Bell is starring in the irreverent, anti-establishment rock musical "Hair" at the 18,000-seat Hollywood Bowl amphitheater in Los Angeles for three shows starting Friday.

"Performing again onstage is wonderful — especially at a venue like the Bowl. It's enormous, dynamic and terrifying," she wrote this week via email. "I never thought I would perform in a place so big!"

Bell, who attended the Tisch School of the Arts at New York University and made her Broadway debut in 2001 in the musical "The Adventures of Tom Sawyer," will play the hippie love interest Sheila and will get to sing "Easy To Be Hard" and "Good Morning Starshine."

Her co-stars include Sarah Hyland ("Modern Family"), Hunter Parrish ("Weeds"), Amber Riley and Jenna Ushkowitz (both of "Glee"), Benjamin Walker ("Abraham Lincoln: Vampire Hunter") Beverly D'Angelo ("Coal Miner's Daughter") and Kevin Chamberlin ("In and Out").

"The process is so alive and energizing and terrifying," said Adam Shankman, who directs and choreographs. He's prepared a staggering 42 numbers for the show, including some nudity, in a rehearsal time that's less than two weeks. "This isn't easy in any shape or form, but it can be very, very fun and very rewarding."

For Bell, who was in a production of "Hair" in college, the move is a welcome one since she's now known more for her roles in Showtime's "House of Lies" and the feature "Forgetting Sarah Marshall."

"I definitely missed singing live and music in general," Bell wrote. "Music heightens any emotion so it is a wonderful tool to use when performing and storytelling."

"Hair," which has book and lyrics by James Rado and Gerome Ragni and music by Galt MacDermot, tells the story of two best buddies who find freedom in the 1960s preoccupation with sex, drugs and rock 'n' roll. The hit songs include "Aquarius" and "Let the Sun Shine In."

Bell together with Tony Award winner Idina Menzel made her own monster hits while recording the soundtrack to the animated film "Frozen." She says she's proud she got a chance to sing in such a landmark movie.

"It's hard for me to conceptualize how many people have seen 'Frozen' — it's been such a whirlwind," she wrote. "I would love it just the same if no one had seen it at all — but the fact that kids are connecting to the idea of choosing love over fear makes me so happy."

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Online: http://www.HollywoodBowl.com

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