After the success of his 2007 musical film Once, Carney wrote the script for Begin Again in 2010 and employed Gregg Alexander to compose most of the film's music. With an US$8 million budget, production began in July 2012 with filming taking place in various locations around New York City. The film premiered in September 2013 at the Toronto International Film Festival and was released theatrically on June 27, 2014, in conjunction with the release of the film's soundtrack. It has grossed over $63 million worldwide and received mostly positive reviews from critics. It was nominated for an Academy Award for Best Original Song for "Lost Stars".
Dan Mulligan (Mark Ruffalo) is a formerly successful record label executive living in New York City who is estranged from his wife Miriam and struggling to keep up with the changing music industry. After being fired from his job, he goes on a drinking binge which leads him to a bar in the Lower East Side where he encounters Gretta James (Keira Knightley). Gretta is a young and fiercely independent songwriter who has just broken up with her long-time boyfriend and songwriting partner Dave Kohl (Adam Levine), a newly successful musician who had an affair with one of his producers' assistants. Captivated by Gretta's music, Dan offers her to sign her to his former record label, and although she initially refuses she reconsiders the offer and agrees.
Dan and Gretta meet with Saul, Dan's business partner and co-founder of their record label, but he does not see the same potential in Gretta and turns her away. Undeterred, Dan proposes that he and Gretta produce their own album together, to be recorded live during the summer at various public locations around New York City. Recruiting a team of talented musicians, including Gretta's best friend Steve, Dan sets out to make an album worthy of being published by his label. During this time, Dan and Gretta bond both personally and professionally, and Gretta takes Dan's teenage daughter Violet, a fledgling guitarist, under her wing and encourages her to play on the album. When the album is finished, Dan and Gretta meet again with Saul, who is very impressed with their collaboration. Gretta demands that Saul give Dan his job back and give her a bigger share in the deal. They leave without reaching an agreement, but Dan feels confident that Saul will eventually sign Gretta to the label.
When Gretta sees Dave accepting an award on television, she criticizes him for selling out to the music industry and she expresses her grievances with him in a song which she records on his voice mail. A remorseful Dave, who is back in New York to promote his new album, returns her call and asks to see her. After some consideration, she decides to meet with him and they critique each other's albums. Gretta feels betrayed by Dave's heavily commercialized rendition of "Lost Stars," a love ballad she had once written and composed for him as a Christmas present, believing that the true meaning of the song has been lost. Dave tells her that the audiences love when he plays it in the new way, and that their energy fills the room. He believes that music is about sharing it with people, but Gretta tells him that's not what she intended for that song. Nevertheless, Dave invites her to come and hear him play the song at the Gramercy Theatre that weekend so that she can see the impact it has had on his fans. She arrives at the venue just in time to watch him play her original arrangement of the song, but as she watches him play and sees the reaction of the crowd to the song and how Dave responds to the fans' adoration by slipping into singing the commercialized arrangement of the song, she realizes that he is a lost cause. Gretta then leaves the concert and cycles through the city with newfound closure and a dawning smile on her face.
Afterwards, Gretta visits Dan at his apartment as he prepares to move back home, having made amends with his wife. She tells him that she does not want him to release her album, instead preferring to distribute it online for $1. Although Dan returns to work with Saul, he agrees to let Gretta release the album online and helps her to promote the release. The next day, Saul jokingly fires Dan for promoting Gretta's album and informs him that it sold 10,000 copies in its first day of release.
- Keira Knightley as Gretta James, a songwriter
- Mark Ruffalo as Dan Mulligan, a music producer
- Adam Levine as Dave Kohl, Gretta's ex-boyfriend and a successful musician
- Catherine Keener as Miriam Hart, Dan's estranged wife
- Hailee Steinfeld as Violet Mulligan, Dan and Miriam's daughter
- James Corden as Steve, Gretta's best friend
- CeeLo Green as Troublegum, a successful rapper who was discovered by Dan
- Mos Def as Saul, Dan's long-time business partner
- Rob Morrow as CEO
Director John Carney conceived the premise for Begin Again several years before he began to write the screenplay in 2010. The story was partly inspired by his own experiences as a musician in a band, and from his impression of the artists and repertoire (A&R) executives of record labels during the 1990s, which formed the basis of Dan's character. Carney wrote the script, which was initially titled Can a Song Save Your Life?, before he, Glen Hansard, and Gregg Alexander began writing the songs; he wanted "to work the music around the story, instead of the other way around."The script's style of featuring songs as a natural element of the story was inspired by the 1954 Judy Garland musical film A Star Is Born, and is also employed in Carney's earlier film Once (2007).Carney first pitched the film in 2010 to filmmaker Judd Apatow, who produced the film alongside Tobin Armbrust and Anthony Bregman whose production company Exclusive Media financed the film's US$8 million budget.
Before casting Keira Knightley as Gretta, Carney considered casting a pop singer such as Adele in the main role, as well as a number of other actresses including Scarlett Johansson, who was at one point attached to the project. Knightley, who had never sung professionally before, prepared for the role by training with a vocal coach and learning how to play a guitar. Mark Ruffalo was Carney's first choice for the role of Dan and agreed to star in the film after Carney sent him the first draft of the screenplay. Singer Adam Levine was also the only person Carney considered casting as Dave, and won the role after talking with Carney over Skype and recording some dialogue as an audition; he declined to be paid for appearing in the film. Although he had had minor acting parts on television before, Begin Again marked his first role in a film. Carney approached James Corden to appear in the film after admiring Corden's performance in the lead role in a Broadway production of One Man, Two Guvnors.
Principal photography of the film began in New York City on July 2, 2012, and lasted for 23 days. Carney chose to film in Manhattan's lesser known neighborhoods that would be more recognizable to locals than tourists. Specific locations included Greenwich Village, the East Village, Times Square, and Washington Square Park. Rather than performing live during filming, the actors sang to pre-recorded tracks. In order to save money on hiring a full crew and extras, some scenes—including one in Times Square—were shot late at night with a handheld camera. The rooftop location near the Empire State Building is located at 28 W 36th St. Carney–Knightley feud During a series of interviews to promote his film Sing Street in 2016, Carney repeatedly criticized Knightley for her acting in Begin Again. When asked about the critical reaction to Sing Street by The Independent, Carney responded unprompted that "it's a small personal movie with no Keira Knightleys in it. It's really rewarding." In the same interview Carney also referred to her repeatedly as a model, despite the fact that Knightley had been working professionally as an actress since childhood, saying "I'll never make a film with supermodels again." He also criticized her in an interview with Heyuguys.com, saying, "I just think with Keira it was like asking her to do something that she could not do." Though he did not specifically name Knightley, he did, in an interview with Den of Geek, say that his desire to make Sing Street came from his "experience of working, let's face it, with a model on my last film". Filmmakers Massy Tadjedin, Mark Romanek, Lorene Scafaria and Lynn Shelton, who had worked with Knightley on other films, tweeted their support for her after Carney's comments.
Carney later tweeted a public apology saying he felt like "a complete idiot" and saying that Knightley was "nothing but professional and dedicated" during the filming of the movie.
- Hailee recorded a song for the soundtrack of the film along with Keira Knightley, Tell Me If You Wanna Go Home.