Glen Hansard and Marketa Irglova in Once Courtesy of Fox Searchlight Pictures

Irglova has known her co-star since she was 13. Every year a music festival has been held in June in her hometown. Six years ago, her parents threw a garden party for the visiting musicians, an Irish rock outfit called The Frames, headed by vocalist and guitarist Glen Hansard. "And that is when we met," recalls Irglova. "They had a gig and Glenn got me up for a song. I was terrified. I really, really didn't enjoy it, but, had I known that it was the beginning of something so amazing, I would have been a little more grateful."

Soon, with Hansard's encouragement and support, Irglova began writing and composing her own music. He was invited back to the Moravian countryside on a regular basis to relax and compose music. Irglova, a multi-instrumentalist, would accompany him on the piano. An ever-increasing number of gigs followed over the next several years. "Making an album as a document of that time was kind of natural." Their creative partnership culminated in 2006 with the release of his first solo album, The Swell Season. "I was very happy to work on it but it was never stated. It just happened," she says.

More things were to happen in 2006. Hansard, who had acted in the Alan Parker film The Commitments, was approached by director John Carney to front a musical movie project about a Dublin street busker whose unexpected relationship with a young street vendor helps kindle his passion for music and songwriting. It had always been Carney's idea to use Hansard's songs in the film, but the lead role was originally earmarked for Irish heartthrob Cillian Murphy. So when he offered the part of the down-on-his-luck singer to Hansard, it seemed only logical to cast Irglova as his muse.

Despite having never acted before, Irglova says she didn't hesitate to take on the role. "I am not an actress. If this project turned out to be not [so] great, it is not like I have a career or anything that I have to take care of. I was hoping I could pull it off for John, just because I didn't want to let him down. But apart from that, I had nothing to lose."

Their chemistry, says Irglova, is one that is felt, not said or expressed. "You just see these two people and you just know that they have got something really beautiful between them, whether it is friendship, or a love affair, or just a musical relationship. They have something powerful between them, a bond. And I think that is what people react to a lot when they see the film. It just radiates that feeling."

Irglova says the experience of being in this film has taught her a lot about acting, but she is by no means mapping out her film and musical career or knocking on studio doors, an remains humble: "So, maybe people will get to hear about this Czech girl who was in this Irish film. I don't know what else should be there. I don't think I am going to get offers." People have heard, and now this gifted ingenue finds herself up for an Academy Award.