WEST HOLLYWOOD, California -- For the sake of more selective filmgoers already developing a headache amid the clamor of summer blockbusters, a little bit of Oscar bait goes a long way. Thankfully, this week had "August" coming early.

A small crowd convened Wednesday night for a preview glimpse of "August Rush," a powerful-looking flick boasting the pedigree of Oscar winner Robin Williams, Oscar nominee Terrence Howard, Golden Globe winner Jonathan Rhys Meyers and Oscar-nominated screenwriter Kirsten Sheridan. Following a half-hour of heart-tugging footage, Five for Fighting singer John Ondrasik took to the stage alongside composer Mark Mancina ("Training Day") and cellist Jen Kuhn to perform key music from the film.

"[Producer] Richard [Barton Lewis] sent me a script like two years ago," Ondrasik told MTV, explaining why he chose the small indie film to be the first he'd ever composed original songs for. "When people send me scripts, they usually want the piano ballad or some sort of '100 Years'/'Superman'-esque type song. But I remember reading this script and going, 'Wow, this is a very ambitious project. It's impossible. No one could ever make it.' In the end, I just wanted to meet the guy who had the balls to give it a shot."

Soon enough, Barton Lewis and Sheridan had convinced Ondrasik that they could pull off the story of August ("Finding Neverland" star Freddie Highmore), an 11-year-old prodigy who hears the music buried within traffic, dribbled basketballs, shoes on the sidewalk and the other things we take for granted. As his troubled, long-separated birth parents ("Waitress" star Keri Russell and Rhys Meyers) search for the son they never knew they had, and Howard's adoption agent stands at odds with Williams' near-mystical guardian of the boy, music ranging from gospel to indie rock to orchestra weave together to tell the three-hanky tale.

"I tend to write a lot of songs that deal with family and kids and stuff like that," Ondrasik said of his contributions to the flick, most of which were putting words into the mouth of Rhys Meyers' troubled Irish indie-rock singer. "[The producer] didn't see Jon's character as Bon Jovi; he saw him as Jeff Buckley -- like I did."

Ondrasik also helped develop the musical stylings of Highmore's August, who learns to play guitar overnight when he adopts a slap-heavy technique that, as they say, you'll have to see to believe. "I said, 'You have this protégé kid who basically learns guitar overnight; what does that sound like to you?' And they didn't come out with [Aerosmith guitarist] Joe Perry, just something that's believable," he explained. "It's more rhythmic. It's more harmonic. You tune the guitar to a chord and you start banging on it."

Early in the film, Rhys Meyers woos Russell's cellist character by crooning some lines a cappella from the classic Van Morrison song "Moondance." For another pivotal scene in the flick, however, Ondrasik had to channel his inner rocker. "This guy is like an indie-rock kind of dude playing low-level rock clubs in New York City. Very hip, very kind of anti-commercial dude," he explained. "With lines like 'I break/ I borrow,' ['Break' is] about coming to the breaking point and trying to hold it together. And then, the final line is, 'I found you.' Which is kind of sarcastic."

At the time he sings it, Rhys Meyers' character is still hung up on Russell's Lyla having left him behind. You'll have to wait until the October 19 release date to find out whether they ever reunite -- but Ondrasik did tell us that the film ends with a potent, unreleased Five for Fighting song that he dusted off for the flick.

"It's called 'King of the Earth,' and we felt it reflected the Robin Williams character, Wizard, who is a hustler in New York," Ondrasik said of the con man who puts August to work in the park and dresses more than a bit like Bono. "He's at the end of the line, and he's a shell of himself, and he sees in August everything he wanted to be. I think 'King of the Earth' reflects some of those sentiments.

"I was supposed to put it on The Battle for Everything," he said of his band's 2004 album. "But after I had the song, I'm like, 'This song can't be song #11 on a Five for Fighting record. It's going to get lost and obscured. I need to really find a special project for this song.' And I kept it in my pocket for two years. ... It's a rock song, but it has the strings. And it has a dark, melancholy lyric to it."

If the whole movie is as strong as the half-hour that the crowd was shown, Ondrasik's tunes will complement some very powerful performances, weaving together a tapestry the Five for Fighting frontman calls "very much a musical."

"There's a great scene where young August is playing a pipe organ in a church," he said. "Then there's an end scene in Central Park, where the orchestra and everything comes together, and you have a big rhapsody. I'd defy you to watch that and not get chills down your spine.

"I don't know if this movie's going to be a huge hit," he cautioned. "But just the fact that anybody's trying to make this? It's great to know that people are taking a swing at it."

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