If not for the fact that her eyes are two different colors (right is hazel, left is blue), Kate Bosworth would be the quintessential all-American beauty—much to her displeasure. “I don’t want to be seen as wholesome,” says the stunning movie star and fashion icon. “To be honest, it’s really annoying.” This month, she graces both the front row of shows during Mercedes-Benz Fashion Week (Sept. 8-15) and movie screens in Straw Dogs (opening Sept. 16), a remake of the 1971 thriller, which sends Bosworth and her cinematic husband (James Marsden) to her character’s sleepy-creepy Southern hometown. There, they’re terrorized by her ex-boyfriend, played by Bosworth’s real-life ex-boyfriend Alexander Skarsgård, best known as hunky vampire Eric Northman on True Blood (HBO, 2008-present).

Offscreen, but rarely off-camera, Bosworth, 28, is a high-profile style-setter who put herself on the map by attending an opening party for her breakout film, Blue Crush (2002), in a deeply ventilated Cavalli dress. A few years later, heads turned when she strolled into a gala for the Metropolitan Museum of Art’s Costume Institute in a head-turning silver drop-waist Prada number, her hair parted at the side and swept off her forehead in a theatrical retro wave. Now, she’s the darling of designers, including Proenza Schouler’s Jack McCollough and Lazaro Hernandez, Derek Lam, Phillip Lim and Rodarte siblings Kate and Laura Mulleavy. They invite her into their showrooms, lavish her with personal attention backstage at their runway shows and often vie for her to wear pieces from their collections or carry their handbags, since doing so instantly grants the item “It” status. Among her personal favorites are Alexander Wang, Jil Sander, Isabel Marant, Stella McCartney, Marc Jacobs, Carven and, of course, Calvin Klein and Coach, for whom she models. Recently, she was spotted carrying a leather Mulberry Carter Camera Bag.

Perpetually in the paparazzi’s viewfinder, Bosworth seems incapable of taking a bad picture, and she’s not averse to appearing in public in baggy jeans and a loose, layered shirt. After she attended the Coachella Music Festival in Indio, Calif., last April wearing a distressed American flag tank top by Topshop, white-denim short-shorts and khaki suede booties, fans clamored to duplicate the look.

Taking her role as tastemaker even further, in 2010 Bosworth and celebrity stylist Cher Coulter took the entrepreneurial step of launching JewelMint.com, an online shopping site offering their original jewelry designs.

Catherine Ann Bosworth was born in Los Angeles on Jan. 2, 1983, the only child of Harold, a retail executive, and Patricia, a homemaker. The family moved frequently before they ultimately settled in Cohasset, Mass. “I grew up in a small town, where everyone wanted to be the same or look the same,” she recalls, but the striking blonde, an outstanding equestrienne by age 13, was in no danger of blending in. She landed the role of Scarlett Johansson’s best friend in The Horse Whisperer (1998) after bringing her “head shot”—a family Christmas photo—to the audition in New York City. Eventually, she deferred her acceptance to Princeton University in favor of playing a competitive surfer in Blue Crush , moved into a house in Hawaii with several cast members, literally immersed herself in training and—somewhat improbably, given her spare frame—maintained an ice cream stash that was off-limits to her roommates. “I insisted that no one touch the Ben & Jerry’s Half Baked,” she recalls. “If they did, it was a full-out showdown.”

Distracted by other cinematic opportunities and an extended romance with British actor Orlando Bloom, Bosworth never did attend college. That “was definitely a hard pill for my parents to swallow,” she admits. “I was the first person in my family to be accepted into an Ivy League school.” Still, she remains brainy; her recent reading material has ranged from The Master and Margarita, a 20th-century Russian riff on Faust, to anything by The New York Times columnist Thomas L. Friedman. With slightly more than a decade in show business, Bosworth has developed an impressive résumé. She’s been in nearly 20 films, receiving prominent billing in both low-budget indies and major motion pictures, such as Superman Returns (2006).

What’s next for this fabulous fashionista? On her agenda are several film projects in preproduction, including Fairytale of New York, a love story about an Irish stand-up comic (Kiefer Sutherland) who meets an American woman (Bosworth) in a New York City art gallery.

No matter the place or project, one thing is certain—Bosworth does everything with her inimitable style.