It isn’t hard to imagine why Glen Hansard and Mark’eacute;ta Irglov’aacute; might have a sweet spot for Los Angeles. The last time the musicians were in town, their song ‘Falling Slowly’ from the Irish indie film ‘Once’ won Best Original Song at the Oscars in a category largely dominated by ‘Enchanted.’ The duo returned to play at the Greek Theatre on Saturday night as the newly formed band The Swell Season, and like their surprise win in February, their performance served as a reminder: Anything can happen in L.A. After the opening act of Iron and Wine, Hansard and Irglov’aacute; were eager to please their fans who were undeterred by the possible chance of rain by playing the songs that catapulted their music careers, including the Oscar winner ‘Falling Slowly’ and ‘When Your Minds Made Up.’ Hansard and Irglov’aacute; were always perfectly in sync and have the same natural chemistry on stage as they did on screen (the fact that they are currently dating might also help). The two also had help from some members of The Frames, a band Hansard has been the frontman of since 1990. But while the film is what made them famous, Hansard and Irglov’aacute; seem to be wary of becoming indie film darlings and want their credentials as musicians to be taken seriously. Instead of opening with a familiar song, they played Van Morrison’s ‘Into the Mystic.’ Only six of the 17 songs they performed were from the film; the rest was new material including new songs ‘Back Broke,’ ‘I have Loved You Wrong,’ ‘Happiness’ and ‘Maybe I Was Born to Hold You in These Arms’ that were characteristically heart warming and tender. However, their conscious attempt to distance themselves from Hollywood wasn’t entirely successful because not only is it difficult to separate their music from the film’mdash;in many ways, their music is the film’mdash;but the gleaming moments of their performance were made of the kind of magic that occurs when the worlds of music and film converge. Before playing ‘Say it to Me Now,’ Hansard told the crowd he would like to perform the song without speakers. Even with the several shouts of disapproval from the crowd who were afraid they wouldn’t hear him, Hansard took his chances and did it anyway. Standing on the edge of the stage with just a faint spotlight on him, Hansard strummed his trademark worn-out guitar and strained his vocal chords to the limit. Whether it was the theatre’s amazing acoustics or the visceral nature of Hansard’s performance, the moment was intimate and hauntingly similar to the film’s opening scene when Hansard’s character, a Dublin street busker, plays the same song to anyone who might hear him. It was perfect in its simplicity, and the several audience members who clapped were immediately shushed. When Hansard had finished, a man sitting nearby yelled, ‘Do it again!’ But the night wasn’t without its setbacks. Like a true Irishman, Hansard shared the stories and ideas that inspired the new songs with long and rambling explanations that were endearing as they were comedic. But some hecklers in the crowd rudely expressed their impatience or even requested old Frames songs, creating strange lulls of awkward silence. Annoyed, Hansard said that he couldn’t see the hecklers clearly from the stage and wasn’t sure if their comments were cheeky or rude. ‘If it’s nice, it’s OK,’ said Hansard. ‘But if it’s mean, do me a favor, and punch them for me.’ It must have worked because the rest of the show went without interruption. In contrast to Hansard’s gregarious and showy manner, Irglov’aacute; is definitely the quiet one who relishes in letting him take over. At one point, she and the members of the Frames left the stage entirely to him. This could easily be written off as shyness, but it wasn’t until the encore when Irglova’s quiet strength as a performer was seen in full force. With a voice just a decibel above a whisper, she sang ‘The Hill’ and ‘If You Want Me.’ Before playing ‘Lies,’ another song from the film, Hansard invited former Frames member and the director of ‘Once,’ John Carney, to play bass. With Irglov’aacute; at the piano, the three driving forces behind the film were together on stage, and the crowd loved it. Then to make the night even more random and unexpected, Hansard explained how the film allowed them to be introduced to all sorts of amazing people, including the man who wrote the music to the Disney classic ‘The Jungle Book,’ and who was in attendance that night. ‘I asked him before the show if he would like to come on stage and play one of his songs,’ said Hansard before introducing Richard Sherman, one half of The Sherman Brothers. Sherman sat at the piano and while I half-expected to hear ‘The Bare Necessities,’ he played, much to the delight of everyone, ‘Supercalifragilisticexpialidocious,’ from ‘Mary Poppins.’ While the crowd clapped and sang along madly like excited six-year olds, Hansard sat on stage off to the side, in utter disbelief. After all, these sorts of things only happen once.