In Begin Againa comedy directed by John Carney, the mastermind behind hit Broadway musical OnceKeira Knightley and Adam Levine play college sweethearts and songwriting partners, while also taking on the ultimate role reversal: she has to sing and he has to act. We caught up with the Oscar nominee and Maroon 5 lead vocalist during the closing night of the Tribeca Film Festival in New York City on Saturday, where they gathered for the film’s U.S. premiere (which was hosted by Chanel) along with co-star Hailee Steinfeld.

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“He didn’t need any acting tips from me, he’s just a sort of natural entertainer and he’s a born actor,” Knightley says about Levine’s first feature film debut. “I’ve never met anybody that has the amount of energy he has at work, he bounces off the walls and you just sort of watch him and go ‘wow!'” Aside from playing a recurring character in American Horror Story: Asylum for the television series’ second season, The Voice coach is a novice when it comes to acting. “You can’t live your life based on what other people might think. You have to do things based on what you think is right for you, and I knew that I could do a good job in this film,” says Levine.

But People’s 2013 ‘Sexiest Man Alive’ wasn’t the only one pushed outside his comfort zone. “My favorite thing about working with Keira was driving her crazy,” says Carney. “She’s not a singer so it was fun to get her to do that. In the end, she gives a great performance and its fun watching her.”

Check out Begin Again when it hits theaters everywhere July 4, 2014.

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