Zooey Deschanel Zooey Deschanel

There's music in the air on the Los Angeles set of Fox's breakout comedy New Girl. Inside the trailer of star Zooey Deschanel, an electric ukulele rests on the couch. "It's my backup from when I was touring," she says. "Sometimes I'll just sing at lunch for people." She even installed a karaoke machine in the show's hair-and-makeup trailer. Creator Liz Meriwether says with a laugh, "I have gone to makeup at four in the morning and there's this music pumping, she's dancing, and I'm like, 'How do you still have enough energy?'"

The cast and crew of New Girl have plenty to sing about these days. The show's premiere episode opened to 10 million viewers on September 20, building on lead-in Glee and benefiting from a bold Fox strategy: making the episode available on iTunes more than a week in advance. "It feels like a different world where what matters is word of mouth and getting awareness out there," says Meriwether. "It was a risky move, and I'm really happy they did it."

The premiere was Fox's highest for a sitcom in 10 years, and since then, it has been this season's No. 1 new show in adults ages 18 to 34. "I've been around a long time and I know to not expect too much because you don't want to get disappointed," says Deschanel. "We're just so happy that people are watching it and sharing this moment with us."

When asked about the key to the show's success, all fingers point to leading lady Deschanel. A veteran film actress (Almost Famous, (500) Days of Summer) and accomplished musician who records with indie guitarist M. Ward under the moniker She & Him, 31-year-old Deschanel is diving headfirst into the world of TV as both star and a producer of New Girl. "I took two years off and did just music, so I really felt ready to come back to acting when I did," says Deschanel, who's also busy prepping a She & Him Christmas album for release on October 24. "I do take being a producer seriously and I love having that responsibility. It actually makes me want to work harder."

That hard work is necessary to meet the sitcom's grueling regimen, which Meriwether describes as 14-hour days, nonstop promotional tours and constant script rewrites. "I'm sure there was a question of, 'Is she going to adapt to this rigorous schedule?'" adds Meriwether of her star. "She completely has, and not only that, she's completely thriving in it."

Deschanel emphasizes the importance of staying creatively satisfied in her career, even if that means carrying a greater weight on her shoulders. "I used to be frustrated on set being just an actor, feeling like I had to constantly keep my mouth shut," she reveals. "It's important to say what you feel in the nicest possible way and tell the best stories we can. That's ultimately my goal."

Deschanel's male costars — Max Greenfield (Schmidt), Jake Johnson (Nick) and Lamorne Morris (Winston) — acknowledge and respect her dedication on  and off screen. "The show is not called Three Roommates, it's called New Girl," notes Greenfield. "She's so talented and because of her, we're all here." And Deschanel recognizes a bond forming between her and the ensemble. "I've always had a lot of guy friends and I like male energy," she says. "We have a good, playful rapport, all of us."

At first glance, it's hard to distinguish the differences between Deschanel and her character, Jess, the slightly awkward but lovable girl next door with striking blue eyes and an affinity for bursting into song at any moment. "She's really a 13-year-old version of myself," says Deschanel. "There's still that part of myself that's totally dorky and weird. There are a lot of people who work hard to be seen as different, but I always wanted to be normal and I never really felt like I was." And how does she feel about the oft-used term "adorkable" permeating the show's advertisements and promotional campaign? "I think it's great!" she exclaims. "But I don't know if I would necessarily describe myself that way."

For more with Zooey Deschanel and the cast of New Girl, pick up this week's issue of TV Guide Magazine, on newsstands Thursday, October 13!

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