Mandy Moore is wearing motorcycle boots. The detail certainly qualifies as strange. As she settles into a booth at a dimly lit Hollywood diner, the kind of greasy spoon where musicians nurse hangovers, it's immediately apparent that Moore is not the preppy good girl you were expecting—nor the wholesome Neutrogena spokesperson, nor the milquetoast star of bland movie fare, nor the erstwhile nineties pop-tart who's remained a professional cutie ever since. Her incongruous footwear is accompanied by a flowered vintage frock, a baggy cardigan, and black tights, and her short, layered hair is just-woke-up mussed. She orders a basket of fries and a chocolate shake, then says, "It's okay to have a milk shake. . . . It is! Whatever! Who fucking cares?"—she'll repeat that last phrase often. In Hollywood, where everyone is cleaning up his or her image, Mandy Moore seems to be set on giving hers a few rougher edges.

To be sure, vestigial hints of her Girl Scout persona remain. Before eating her fries, Moore, who lives nearby in Los Feliz, daubs her hands with lavender-infused sanitizer. "I'm a germ-phobe when I meet a lot of people or shake a lot of hands. I always have hand sanitizer and alcohol swabs," she says, "so I can sort of go back and forth between the two." She explains that she added alcohol swabs to her handbag when her "best girlfriend," a publicist for Coach ("you know, the handbag company"), informed her that "you can build up an immunity to the antibacterial stuff—and I was like, Oh, perfect." In the process of disinfecting, Moore removes her conspicuous engagement ring, an enormous tear-shaped diamond—a gift, the world now knows, from Ryan Adams, whose indie cred can be measured in numerous reports of his substance abuse and onstage tantrums. It's hard not to wonder, of course, what role Adams might have played in Moore's alt-chick reinvention.

After all, her aesthetic transformation is coinciding with a musical one. Moore, who's best known for the appropriately named 1999 single "Candy," has spent the better part of the past year cowriting and recording with singer-songwriter-producer Mike Viola, a musician's musician with a cult following. The result is Amanda Leigh, a collection of acoustic rock that variously channels Todd Rundgren, Joni Mitchell, and Paul McCartney. "The music is all a reflection of me now, not somebody else's choices," Moore says, taking an oblique jab at Epic, which released her first four albums. "If people don't like the music, then they don't like me—and that's quite all right." Now 25, she's made a point of trashing her bubblegum-pop past, calling her early output "trite," "blah," and "crappy." As she says, "I was just told to show up and what to sing. . . . That was late-nineties pop music for you." She's reverential about her fellow pop divas, however, and saves the deprecation for herself. "I found myself in the company of Britney Spears and Christina Aguilera, who had really quality music, much more so than mine was," she says. "I'm sure there are people scratching their heads, going 'Wow, how is she still around?'"