Gregg Alexander, 2014
Robert G. Zuckerman

In the 15 years following Gregg Alexander's run in the Billboard Hot 100 with New Radicals' ebullient pop gem "You Get What You Give" -- which peaked at No. 36 but hung in for 20 weeks -- his life has been one of privacy. Having forsaken live performances and recording under his own name, he has remained a songwriter and producer bouncing between London, Los Angeles and Nashville, using aliases on occasion and scoring a major hit with "Game of Love," the Santana-Michelle Branch recording that earned Alexander a Grammy.

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His return to the limelight has come through the Keira Knightley-Mark Ruffalo-Adam Levine film Begin Again, writing the score and songs for Knightley's songwriting character. "Lost Stars," the song Levine and Knightly sing separately in "Begin Again," is the first tune to receive an Academy Awards/Golden Globes push from the film's distributor, the Weinstein Co. When the film opened June 27, grossing $16.2 million domestically, the limited promotional activities were handled by the stars and director-writer John Carney, who was basically asked to compare the film to his previous music-centric picture, Once.

"I wanted to take a backseat when the film first came out," says Alexander, "but now that there is a little bit of energy and support for the music, I'm in."

Alexander, a tall, jovial and unassuming man of 44, is starting to work the campaign trail, performing "Lost Stars" at the Hollywood Music in Media Awards on Nov. 4, speaking at the Billboard + Hollywood Reporter Film and TV Music Conference on Nov. 5 and doing his first interviews in 15 years with Billboard and The Hollywood Reporter. "Lost Stars" stands a reasonable chance of nominations considering this year's wide-open field in no way resembles last year's combination of hits (Frozen's "Let it Go," Pharrell's "Happy"), major stars (U2, Coldplay, Taylor Swift) and a quirky indie artist (Karen O).

His journey with film, which was originally titled Can a Song Save Your Life, started four years ago with songwriting sessions in the south of Spain with his collaborator of nearly 20 years, Danielle Brisebois.

"I found this screenplay so compelling. It really got to me, and I would try to honor what was on the page," says Alexander. "I thought it would be exciting and fun to do a body of work instead of just a song."

They memorized the script and spent six days, mostly dining on fresh sardines in the Costa del Sol region, before writing the songs that would ultimately become the album that Knightley's character Gretta records with Ruffalo's washed-up producer character. "Lost Stars," which Gretta writes, is the song she gives to her ex-boyfriend, played by Levine, intended as a pop hit.

"I was under the impression -- or illusion -- that the spirit of the characters were in me, hopefully to the point where I could write something they could sing without self-editing," he says.

"'Lost Stars,' more than any other song in the film, was the one where you wanted to get out a philosophy that Keira's character would sing but Adam would relate to and something that would also touch a contemporary audience. At the end of the film, it's a young audience watching this song that really has a lot of pathos and pain in it, but yet people are doing this," he says, raising his arms above his head to do a slow wave.

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Brisebois says their days spent going for walks and hanging out helped "cracked the code of an epic song that is really organic and heartfelt. John Carney said, 'You've got to write a song that will save someone's life.' No pressure there. We challenged each other, and in some ways, it feels like hats off to our friendship, being able to create something like this together."

Alexander and his team, which included fellow songwriters Nick Lashley and Nick Southwood, worked 50 days straight to finish the recordings prior to the film's three-week shoot in the summer of 2012.

"Overall, it was the same philosophy as always: Desperately try to write the best song you can. And I've always been the obsessed studio creature -- I could sped six months getting a song right, but I wouldn't want to spend six days getting the show right," he says. "There's a certain rawness to some of the performances because we were under a bit of a time crunch. Keira is not technically a singer, so it was great to see her relentless passion and hard work combined with her great tone. It's a very charming voice and it draws you in in a great way."

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An intense music enthusiast with strong opinions on everything from production techniques to the value of underappreciated '80s music, Alexander has a specific list of records that he says set the gold standard for quality. Check out his list and listen in Spotify below:

1. "Goin' Out of My Head" - Little Anthony and the Imperials
2. "I'll Be Around" - The Spinners
3. "Don't Stop Believin'" - Journey
4. "You Are Everything" - The Stylistics
5. "Shining Star" - The Manhattans
6. "The Beautiful Ones" - Prince
7. "Jimmy Mack" - Martha and the Vandellas
8. "Train in Vain" - The Clash

He also has a short list of the songs that changed his life.

"Baba O'Riley" - The Who
"Hey Jude" - The Beatles
"Let's Go Crazy" - Prince