Kate Voegele did not set out to confuse the heck out of people by playing a singer-songwriter named Mia on One Tree Hill who sings, well, Kate Voegele songs. And yet… "It’s simpler than it sounds," the 22-year-old insists. "I play Mia on the show. We make the same records. Mia’s making her second record, and Mia’s second record is A Fine Mess, which is also my second record." So why not just play Kate Voegele then? "It seemed like the best way to do it," she says. "Because if I played myself on the show, it would confuse people more that the storyline wasn’t necessarily my life."

The show itself isn’t helping clear up the confusion when, for instance, it shows a shot of Mia’s album cover — and it looks exactly like Voegele’s, but with Mia’s name. What it does help, though, is sell albums and concert tickets: She went from an unknown teenage singer to No. 4 on the iTunes chart when Tree Hill cast her last season as the first artist to sign to Peyton Sawyer’s record label. And that experience has intertwined her second album with the show in ways she never dreamed of. "The other night, One Tree Hill featureda song called ‘Angel,’ and I wrote that song in my trailer when we wereshooting season 5," she says. "It was really cool: I wrote this song onOne Tree Hill and now it’s the coda song on One Tree Hill." The show’s music geek creator/exec producer, Mark Schwahn, routinely works with Voegele to incorporate her tunes into scripts. "They really look out for me and make sure fans know what’s going on," she says. "It’s really an incredible thing that they’re so passionate about music that they’re willing to do all that to support an artist they believe in."

The May 18 finale will feature an entire scene promoting A Fine Mess — which comes out the same day — with Mia signing copies of the album at a North Carolina Best Buy and preparing to go on tour. Which raises a question: What will become of Mia and bartender Chase (Laguna Beach‘s Steven Coletti), whose relationship has just started heating up? "They’ll have to do the long-distance thing," she says. "That’s definitely something that isn’t easy."

More from EW’s Music Mix:

Embarrassing albums: What are your most shameful musical secrets?
Take on Me: What are the best–and worst–cover songs?
‘American Idol’s’ audience is aging: Do guests like Jamie Foxx and Lady GaGa help?
The Return of Sugar Ray: They just wanna fly, again — this time with ‘Cougars’