Robert Sebree

Backstage at the Greek Theatre, Juliette Lewis is one hot mess. After opening for the Pretenders and Cat Power, the singer-actress’ dark, choppy hair clings damply to her neck; smeared glitter eye shadow sparkles on her cheeks; and the toe of one boot (black with vaguely Victorian gold buttons up the sides) is held together with tape. The centerpiece of her ensemble — a red, single-sleeved romper made of metallic Lycra and sequins with a regal plume of feathers at one shoulder — looks like the result of a collision between Motley Crue and the Moulin Rouge.

It’s hard to say who, exactly, she most resembles: the pout and smudged eyeliner are pure Mick Jagger, the feathers are a bit Brian Eno and Lewis herself name-checks Mad Max. One thing for sure: She looks like a rock star should.

“I finally got a real stylist!” says Lewis excitedly, sipping tea as friends come up to offer hugs of congratulations and her mother and sister/manager Brandy Lewis mill about. “It’s funny now to see this stuff as art,” she continues, holding out the cascade of patterned fabrics that hangs from her waist, “because for so long I always fought against it.”

If Juliette Lewis is embracing her inner fashionista, you can bet it’s going to be interesting. She is, after all, the actress who attended the 1992 Academy Awards (nominated for her role in “Cape Fear”) with Brad Pitt at her side and stark cornrows in her hair — a look that earned her a permanent spot on many “worst dressed” lists. But to paraphrase legendary fashion doyenne Diana Vreeland, a splash of bad taste is far better than no taste, and the funky combos Lewis puts together — like the neon pink tights, blue lace teddy and Indian feather headband she wore in her “Hot Kiss” video in 2006 — have a way of turning into tomorrow’s trends.

Three years ago, the star of “Natural Born Killers” and “Strange Days” stepped away from acting to devote herself fully to her music, but this fall the 36-year-old actress is back with a juicy mean-girl part in Drew Barrymore’s roller derby flick, “Whip It,” which opens Friday. In addition she has a new album, “Terra Incognita,” and a headlining tour across the U.S. and Europe that will keep her on the road until December (with an Oct. 17 stop at the El Rey Theatre). Between press, promotion and performances, it all adds up to a whole lot of wardrobe changes, and Lewis has been working with Marina Toybina, who designs under the name GLAZA, to help her “up the ante visually.”

Recent TV appearances have certainly done that. For a BBC interview, Lewis wore a fitted blue vintage leather jacket over a gray blouse with an elaborate, oversized flower at the neck, tight trousers and tall boots — “sort of equestrian looking but more fun,” says the native Angeleno. The outfit she wore on “The Late Late Show With Craig Ferguson” — oil slick-shiny black leggings, a black-and-red GLAZA top with ruffles down the front and (fake) fur tufts at the shoulders, plus jewel-studded booties on her feet — prompted the talk show host to proclaim, “You’re like a sexy leprechaun from another planet!”

Naturally her “Late Late Show” performance of the frenetic, careening single “Fantasy Bar” required another costume change — this time into a suede fringed vest with enormous feathered epaulets over a black bustier, sequined hot pants, and electric blue Lycra leggings.

Lewis’ last two albums — and her look — were more raw, lean and stripped down. But she describes “Terra Incognita,” recorded with a new band and produced by the Mars Volta’s Omar Rodriguez-Lopez, as an embrace of duality: “the vulnerability and the lion’s roar . . . the disillusioned spirit along with the eternal optimist.” And she says the Moscow-born, Fashion Institute of Design & Merchandising-trained Toybina creates “an extension of what the music is, the ethereal, dreaming guitars mixed with that earthy, big-bottom drumming . . . what does that look like?” Despite the wild mix of synthetic and organic textures, the silhouette is consistent: “stuff that wraps tight, strong legs, and then the big shoulders like a buffalo.” She giggles. “I didn’t even intend to be current, but I guess that’s kind of popular right now!”

Lewis wore some of Toybina’s couture creations in a photo shoot several years ago, but they’ve formally worked together only since August. Both seem giddy about the potential of the collaboration.

“She’s a visionary; she manifests dreams,” says Lewis. “And I don’t mean to be so lofty, but it’s for real.”

“She kind of gave life to my pieces,” Toybina returns. “This was somebody that I could express my art to. . . . Not everybody will wear a wire dress.”

Of course it isn’t all feathers and flash and wire dresses. “I look at Juliette as somebody with multiple creative personalities,” explains Toybina, who will mix classics with vintage finds and avant-garde silhouettes, often adding the final flourish of a killer shoe.

“She knows I’ll go the extra step,” Lewis says approvingly. “There are those actresses that are very streamlined, very polished . . . right out of a magazine. I like sophistication, but I also like something that’s always a little amiss.”

For the “Whip It” premiere at the Toronto International Film Festival, she skipped the typical frock in favor of high-waist black satin pants from CNC paired with a bell-sleeved silk blouse and rakish hat picked up at the Reiss boutique in Heathrow Airport. Pink Moschino booties with black polka dots completed the look. Overall, it was a little disco, a little deco, a little daffy and totally original.

When she has time, Lewis says she enjoys the “discovery” of shopping, and she isn’t secretive about her sources, either: She raves about her new go-to vintage shop, Sielian’s in West Hollywood, where she scored a Missoni dress that was a hit in Paris and another black-and-white dress by a designer whose name she forgets.

Lewis loves fashion fantasists like Galliano and Alexander McQueen, but for the most part, labels matter very little to her. She’s happy to support pals such as Whitley Kros designer Marissa Ribisi, and she was flattered, not being “of that scene at all,” by an invitation from Phillip Lim to his show in New York and to a CFDA/Vogue Fashion Fund dinner last fall. Now he’s among her favorites. “He’s so inventive with the details he puts on a dress!” she marvels.

This month she and Toybina found time between Toronto and the tour to check out G Star Raw’s Spring 2010 show in New York, where the standout piece was a white military jacket. “We thought, what a beautiful blank canvas,” says Lewis. “We’re gonna go and bedazzle it!”

After “Whip It,” Lewis’ next on-screen appearance will be in Mark Ruffalo’s directorial debut, “Sympathy for Delicious,” which is expected to show at the Sundance Film Festival in January. She plays a drug-abusing bass player in the indie drama and says Ruffalo was an “incredible revelation” as a director. “We had a profound creative experience. I think I did something exciting; he does [too].”

Yet no matter how intense a film role, Lewis reveals there is still “more of this creative fire that gets unused.” Forget the Oscar-caliber dramas; her ultimate dream is to combine her rock star and acting lives by touring with sets and a lighting technician, and then bringing to the screen a rock ‘n’ roll fantasy worthy of Fellini or Terry Gilliam. “People associate me with this deep, dark stuff,” she says, “but what really knocked my world apart was ‘All That Jazz.’ It blew my mind as a youngster, and things like ‘Hair,’ ‘Rocky Horror Picture Show’ . . . . More and more you’ll see that that’s who I am.”