Toronto: 'Can a Song Save Your Life?,' With Keira Knightley and Mark Ruffalo, Takes Fest by Storm

'Can a Song Save Your Life?'

Keira Knightley is Gretta, a heartbroken New Yorker that just got dumped by her musician boyfriend, played by Maroon 5's Adam Levine. A down-on-his-luck record producer (Mark Ruffalo) recognizes Gretta's musical talent and opens up an entire city of possibility.

TORONTO -- I caught 12 Years a Slave and Gravity last week at the Telluride Film Festival, so the following declaration is a little bit of a cheat, but the best film that I've seen at the 2013 Toronto International Film Festival, thus far, is John Carney's Can a Song Save Your Life? The charming romantic-drama, which I caught at its world premiere on Saturday night at the Princess of Wales Theatre, revolves around musicians during times of transition and features beautiful original music -- just like Carney's last, Once (2006), which was awarded the best original song Oscar for "Falling Slowly." This time, though, he has a slightly larger budget and big-name stars: Oscar nominees Keira Knightley, Mark Ruffalo, Catherine Keener and Hailee Steinfeld, plus musician-actors Maroon 5's Adam Levine (making his big screen debut), Mos Def and Cee-Lo Green. The audience offered large ovations when the film ended and when the director and stars took the stage for a post-screening Q&A.

PHOTOS: The Scene at the Toronto Film Festival 2013 

If and when this film gets picked up for distribution -- perhaps by Fox Searchlight, which distributed Once and was heavily represented at Saturday night's screening -- the only question about its awards prospects will be whether they will apply to this year's or next year's race. 2006 best actress Oscar nominee Knightley (Pride & Prejudice), I would argue, is the film's lead, and is terrific as always, demonstrating not only acting chops but also a truly lovely voice that I didn't believe was hers until Carney confirmed it after the film. (It turns out she also sang in the little seen 2008 film The Edge of Love.) But, for my money, Ruffalo steals the show with a complex and endearing supporting performance that could earn him an Oscar. God knows he's been worthy of one on at least two occasions in the past, with You Can Count on Me (2000), for which he wasn't even nominated, and The Kids Are All Right (2010), for which he was -- but he's even better in this film. And he's the sort of actors' actor and stand-up guy whom the community would love a good excuse to recognize.

In the film, Knightley plays a Brit in America who has been seriously dating a fellow singer-songwriter for five years until he strikes stardom and cheats on her, leaving her devastated and prepared to return to England. The night before she is to fly back, however, she is dragged by a friend to an open-mic nightclub and pressured into performing her latest effort. Fatefully, in the audience that night there happens to be a talented but down-on-his-luck music producer, played by Ruffalo.  He is an alcoholic and, at the moment, on the outs with his boss (Mos Def), wife (Keener) and daughter (Steinfeld). But he is still perceptive enough to sense great potential in Knightley's character and sets about trying to convince her to work with him. They decide to team up, for lack of better options, and aim to help each other not only face the future, but mold it according to their dreams.

PHOTOS: The Scene at the Toronto Film Festival 2013

The film, which was largely improvised, is not just a rom-com -- although some may see some similarities between it and another Knightley pic, Love, Actually (2003). It is also a beautiful ode to New York City, a meditation on the tortured life of artists and a celebration of what music is really about, or should be. It would make for a killer double-header with Inside Llewyn Davis, a 2013 awards hopeful that focuses on another lost soul who is equally fascinating but possesses a bleaker worldview than these two beautiful spirits, who I defy you to not fall in love with.

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