Tribeca: 'Begin Again' Stars Keira Knightley and Adam Levine Talk Challenges of Singing, Acting

Evan Agostini/Invision/AP
From left: Hailee Steinfeld, Keira Knightley and Adam Levine at the Tribeca Film Festival closing-night screening of "Begin Again."

The producers and cast also weigh in on the new title for Toronto hit "Can a Song Save Your Life?"

In the music-driven indie Begin Again, both Keira Knightley and Adam Levine take on new roles, with the former singing and the latter making his feature film debut as an actor.

Ahead of the movie's closing-night screening at the Tribeca Film Festival, Knightley and Levine both admitted to The Hollywood Reporter that they didn't know what they were doing.

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"I think I just blocked it out of my head until I actually got into the studio and then went, 'Oh f---, I have no idea how to do this,' " Knightley said of singing in the movie. "And I was very fortunate because there were some lovely people who held my hand, and we just worked it and worked it until we found something that was all right."

Levine said that his biggest challenge with his first acting role in a movie was "learning how to act."

"I literally had to pretend that I knew what I was doing, in pretending to be another person," he explained, pointing out that it was "very meta."

Levine credited the film's writer-director John Carney, who previously wrote and directed Once, for bringing him to the project, explaining that Carney called him and asked him if he wanted to do the movie.

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"He thought about me, and I was flattered," Levine said. "It kind of just happened, and I'm not sure how. But I credit him completely because him believing in me was 100 percent of why this ever happened."

Carney was also responsible for Begin Again being set in New York, producer Tobin Armbrust explained.

"John wrote it for New York, and I think he has a real fondness, more of a love affair, for the city," he told THR. "And the beauty of it is he directs it almost like he's discovering [the city] with us as an audience. So I think the energy of it, the fact that it's an A&R guy from a certain time period, he liked all of that. He felt like there was no place other than New York where you could pull this off."

In introducing the film, Harvey Weinstein, who quickly snatched up U.S. rights to the title -- despite strong interest from rival buyers -- at the Toronto Film Festival, called Begin Again, "an iconic New York film."

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"It's about the music business in New York City; it's true to the roots of New York City," Weinstein said, speaking after Tribeca co-founders Robert De Niro and Jane Rosenthal and welcoming New York City mayor Bill de Blasio to the screening.

Since The Weinstein Co. acquired Carney's film, the title has changed from its Toronto moniker, Can a Song Save Your Life?

On the red carpet at Tribeca, producer Anthony Bregman commented that while they were testing the film, they found that audiences hated that title.

"We'd been testing the movie throughout the fall and into the winter, and it's been testing consistently -- incredibly well across four quadrants in an exciting way. But the title was unilaterally disliked by everyone," Bregman noted. "It was getting an 11 percent approval rating, which is pretty low … a lot of people said it sounded like a different type of movie, like a softer movie than it was. They just hated the title."

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But Bregman admitted that Can a Song Save Your Life? was more of a working title that Carney used to remind himself what the film was about.

Knightley and co-star Hailee Steinfeld both said that they felt fine about the change, with Steinfeld remarking, "It definitely fits, just as the other one did."

Since the film premiered at Toronto, the heads of its production company, Exclusive Media, have both been ousted. But Armbrust, who also works for Exclusive, said that wouldn't have any impact on the film.

"We made this movie two years ago, and we're releasing five movies this year, so none of those are affected," he said.