By Simon Vozick-Levinson
Updated September 23, 2010 at 07:13 PM EDT

Image Credit: Jay West/WireImage.comThe young women who are lining the aisles of Austin’s Waterloo Records all seem to have one question on their minds. “Is he still coming?” someone murmurs. “Are you sure?” The crowd of around 150 fans explodes in cheers when Bruno Mars arrives promptly at 5 p.m. for an in-store performance and launches into “Nothin’ on You,” his chart-topping duet with Atlanta rapper B.o.B. The baby-faced Hawaiian singer-songwriter-­producer, 24, is all smiles in a white T-shirt, a varsity jacket, and his signature fedora. Posing for pictures with smitten admirers after the performance, he pauses only briefly when asked how he is feeling. “Look,” he says. “I’m happy now.”

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Less than 48 hours earlier, Mars was locked up in a Las Vegas jail. ­He was taken into custody early on Sept. 19 after police allegedly found him with 2.6 grams of a narcotic (they believe it was cocaine) in a bathroom stall at the Hard Rock Hotel & Casino following a performance. According to the police report, he “admitted he did a foolish thing” when questioned by the arresting officer. (Reps for Mars declined to comment on his arrest.)

It was a surprising development during what should have been a period of celebration. Six days earlier, Mars had taken the stage at the MTV Video Music Awards, capping off a stunningly successful summer run: In addition to “Nothin’ on You,” he has co-written, co-produced, and sung on Travie McCoy’s smash single “Billionaire”; co-written and co-produced Cee Lo Green’s profanely catchy viral phenomenon “F— You”; and scored a solo smash of his own with “Just the Way You Are,” currently No. 1 on Billboard’s Hot 100. With his debut ­album, Doo-Wops and Hooligans, due in stores Oct. 5, he is now closer than ever before to completing his lifelong project of becoming a megastar — unless, that is, his unexpected legal drama brings it all crashing down.

When not on stage, Mars spends most of his time at Levcon Studios, the cluttered Hollywood clubhouse where he and production/writing partners Philip Lawrence and Ari Levine (collectively known as the Smeezingtons) have ­created Mars’ best-known work. A week before his arrest, he’s at Levcon as usual, feeling on top of the world. “I’m here from when I wake up to when I go to sleep, about six days a week,” he says, stretching out on a couch under a framed Billboard chart with “Nothin’ on You” at No. 1. Lately, he’s been working Sundays, too. “I haven’t had a day off in a long time. But I can’t complain. I’ve been chasing this s— forever.”…

To read the rest of this story, pick up the latest issue of Entertainment Weekly tomorrow, Sept. 24.

Additional reporting by Karen Valby.

(Follow the Music Mix on Twitter: @EWMusicMix.)

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