Los Angeles, California (CNN) -- She looks like Rock 'n' Roll Barbie -- cascading blonde locks, cute little upturned nose, a cherry red electric guitar she calls "Pepper." Then she rips into the solo from "Beat It."
All images of a plastic doll shatter into a million ear-splitting decibels. As tiny fingers tipped in blue nail polish attack the frets in a blur, you understand why Michael Jackson cast 24-year-old Orianthi as the guitarist on his "This is It" tour. The girl shreds.
"Getting to come in and audition for him, I'd never been that nervous in my life!" she recalls in an Aussie accent. "Going in and playing the 'Beat It' solo for him -- and he was just sitting on the couch staring at me -- it was very intense, and I was just praying to God I got it right."
Her debut album, "Believe," hits shelves Tuesday -- the day before the Jackson documentary, "This is It," arrives in theaters. The film chronicles the last few weeks of their rehearsals before Jackson's death on June 25.
"I really want to see it," she says. "It's going to be hard for all of us. He was our leader. It was so devastating."
One of the haunting early clips from the movie shows Jackson strutting over to Ori as she plays -- her long hair blowing in slow-mo while he dances ethereally beside her. But this wasn't the first time she'd taken the stage with a high-profile singer. In February, she had audiences asking, "Who's that guitarist?" when she accompanied Carrie Underwood at the 51st annual Grammy Awards.
"It was pretty insane to play the Grammy Awards, and looking out in the audience and seeing rock royalty -- Bono and Paul McCartney. It was crazy," she remembers.
Orianthi Panagaris first picked up an acoustic guitar as a six-year-old in Adelaide, on the southern tip of Australia. "My grandmother is Orianthi. She's from this small island in Greece. I'm half Greek, half Australian," she says.
Ori switched to the electric guitar when she was 11, after seeing Carlos Santana headline a concert in her hometown.
"I begged my dad to get me a secondhand electric guitar so I could be like Carlos," she says. To this day, one of her favorite instruments is a Paul Reed Smith Custom 24. Not coincidentally, Santana's guitar of choice is Paul Reed Smith.
When she was 18, she joined him on stage in Adelaide for part of a set, even trading licks with him in a duet. Since then, other legendary musicians have come calling. "I got to jam with Prince, which is amazing. Getting to write a song with Steve Vai -- he was my first support," she says. Share your reviews, thoughts on "This Is It"
Orianthi's debut album is a cross between sassy Avril Lavigne-esque pop numbers and more anthemic rock tracks in the vein of Paramore or Evanescence. On disc, it might be easy to lump her into the same category as other young singers. But live, you're reminded that Ori herself is playing lead guitar, and that the searing guitar riffs aren't courtesy of an anonymous studio musician who's been hired for his or her chops. She also wrote or co-wrote nine of the album's 11 tracks.
"I've been overseeing, writing my record and recording for two and a half years, and I'm [very] proud of it," she says. "I just hope kids can come to our show and just be inspired to get home and pick up their guitars -- or ask their parents to buy it for Christmas. You know, drive their parents batty, and crank it up and rock out."
And with that, she excuses herself to tune her guitar for rehearsal.