Dress and necklace, Vionnet (prices on request). Birds of Paradise Volutes necklace, Van Cleef & Arpels (price on request). Bal Harbour Shops, 9700 Collins Ave., 305-866-0899. Open lantern hinged cuff, House of Waris ($5,020). The Webster, 1220 Collins Ave., Miami Beach, 305-673-5548. Bois de Rose bracelet, Dior ($30,000). Saks Fifth Avenue, Bal Harbour Shops, 305-865-1100. White-gold and diamond Spiga bracelet, Bulgari ($13,300). Bal Harbour Shops, 305-861-8898. Cuff, Tom Ford (price on request). Neiman Marcus, Bal Harbour Shops, 305-865-6161

Elettra Wiedemann has been up since 4:15 AM, but the face of Lancôme is none the worse for wear, even as the afternoon begins to dip into twilight. The reason for Wiedemann's early start wasn't a predawn fashion shoot, although she's had her share of those, but something more prosaic: an intense swim workout. A routine exercise session to keep her photo-ready trim? No, the grueling hours of lap swimming were to prepare her for the Nautica South Beach Triathlon, to be held in Miami early new month.

"It's my first triathlon, and I find it exhilarating,” she says about her plans to participate in the annual sports event where nearly 3,000 athletes compete in ocean swimming, biking, and running to benefit St. Jude’s Children’s Research Hospital. Though she has often traveled to South Beach for fashion and advertising campaigns, this will be the first time she’ll be running and cycling through its streets. “I always love to go to [Miami]. It’s such a relief when you come from New York City. The pace and vibe are so different.”

Still, it’s hard to imagine that Wiedemann doesn’t keep to a hectic pace no matter where she travels. The rigorous athleticism is just one aspect of the protean lifestyle the 28-year-old has forged for herself. Indeed, in addition to her elite status in the fashion world (besides being the face of Lancôme, she has appeared on numerous covers of the international editions of Elle and worked with such top photographers as Bruce Weber and Gilles Bensimon), she also has enjoyed eclectic success as a scholar (with a bachelor’s degree in international relations from The New School and a master’s in biomedicine from The London School of Economics and Political Science), a philanthropist (she is a cofounder of the global charity One Frickin Day), and a restaurateur, having launched Goodness, a four-day “pop-up” eatery that featured a different celebrity chef daily during New York’s annual Fashion Week.

In the course of an interview, it becomes clear that the push for such wide-ranging achievement stems from a desire to prove herself worthy of her bloodlines. It’s a striving that simmers below the conversational surface even as she downplays her sterling pedigree as the daughter of Isabella Rossellini and granddaughter of the legendary actress Ingrid Bergman. Though Wiedemann once rebelled against her family’s fame, she is much too well brought up—or resigned—to show any irritation when the subject inevitably is raised.

“I’m a very independent and ambitious person, and I felt constantly hounded by it,” she says of the celebrity-by-association shadow from which she has had to emerge since Weber chose her for the 2003 Abercrombie & Fitch campaign. “No matter what I did, it always was being interpreted through the lens of somebody else’s influence and interests, and that got incredibly obnoxious. I was so angry and annoyed that I wouldn’t let journalists ask me about my family.” The day-to-day intrusions particularly rankled. “My mother often was stopped on the street, and I was very protective of her,” she says. “She was always much too gracious and generous.” But she realizes now that “getting to be known for yourself takes time. “If my 28-year-old self was to speak to my 20-year-old self, I would say, ‘Don’t change anything; stay focused, and it will come.’”

While it took time to develop a certain sangfroid to deal with her family’s fame, she says the drive to succeed came much earlier. A childhood illness propelled her as much as her mother’s and grandparents’ shining accomplishments. At the age of 12, Wiedemann was diagnosed with scoliosis, a painful and debilitating curvature of the spine from which her mother also had suffered. Having to wear a back brace 23 hours a day for six years, she says she still has scars from the massive blisters, where the skin was rubbed raw by the brace’s pads. “I was devastated; that’s exactly the age when you don’t want to have a back brace,” she recalls. “Your body is changing, you already feel gross and awkward, and kids are cruel.”

She says her dad, Jonathon Wiedemann, was critical in helping her get through this rough period. She freely admits to having an “excessive love of a father,” the psychological complex identified with her namesake, Electra, the tragic princess of Greek mythology who avenges the murder of her own father, Agamemnon. “I wouldn’t take it that far,” she says with a laugh. “But I do have a major, major tie with my father. My mother and I are incredibly close, and she was a great mom. But her career was peaking when I was born, and she was away a lot. My dad and I have so much in common, including a love of sports.”

Jonathon Wiedemann was still in college when he met and married Isabella Rossellini, who was nearly 10 years his senior. A former model, he is now a Microsoft executive living in Seattle with his second wife, Thury Gudmundsdottir. As Elettra grew up, he acted more like a “big brother,” indulging his daughter by serving ice cream for breakfast, playing Beatles songs at top volume, and jumping on the beds with her. “My mother was the disciplinarian—no elbows on the table, don’t speak with your mouth full—but my dad had a lot of playful, endearing qualities,” she says.

When she was diagnosed with scoliosis, it was her father and paternal grandparents—Fred Wiedemann and his wife, Florence, a Jungian psychologist— who helped her forge a steely will and determination. “They didn’t let me get away with self-pity,” she recalls. “They were nurturing and loving, but believed that when something bad happens, you have to suck it up. Get over it. I remember my dad saying, ‘Listen, you can get out of this brace. Just swim, every day. You have to, or your muscles are going to atrophy.’ Since then, I’ve had a very healthy relationship with exercise, working out five days a week. I really didn’t appreciate that until I started to swim competitively. There’s always a reason for something, even if it’s 20 years out.”

Wiedemann says that while she was keen to succeed at whatever she attempted, she had no desire for fame. And although both her maternal grandparents, Ingrid Bergman and the great neo-realist director Roberto Rossellini, had passed away by the time she was born, the ambivalence about their celebrity still lingers. Wiedemann says she hadn’t seen her grandmother’s classic, Casablanca, until she attended a 60th anniversary screening in 2002. And she’s sampled only a handful of Rossellini’s films. “I admire the talent and understand their place in history,” she points out. “They’re really good movies, but there are old movies that I enjoy more, like Vertigo,” she says of the Hitchcock classic starring Kim Novak. “I could watch that once a week and never get sick of it.”

Still, there was the legacy of accomplishment. Given her place in an overachieving family—fluent in French and Italian, she is the oldest of five, which includes her adoptive brother Roberto and three half-siblings from her father’s second marriage—Wiedemann says that she felt the “need to prove herself” but was very insecure how to go about it. She developed an early interest in animal welfare (a passion she shares with her mother), something fueled by her visits to White Oak Plantation, a private animal preserve outside Jacksonville, Florida, owned by a family friend. She found it to be the perfect respite from New York City, where she grew up, and from her first visit was enchanted with the place, sleeping with cheetahs and giving rhinos belly rubs.

Wiedemann recalls her early 20s as “a very difficult time. I felt unfocused and was very hard on myself. I felt I was never going to get it.” Salvation, of sorts, came through modeling, which she says she “fell into,” intending to do it “only until the phone stopped ringing.” In fact, she says, a “horrible” picture of her recently surfaced on the Internet, which showed her at a model casting early on in scruffy jeans and a T-shirt. “It showed how little I gave a damn about all this stuff.”

Nearly a decade later—with intermezzos to earn her college degrees—she finds herself a top star in a profession that she is now embracing. Wiedemann has used her leverage in that world on behalf of her avocations: healthy eating, with her restaurant, Goodness, and philanthropy, cofounding the charity One Frickin Day with her fiancé, British businessman James Marshall, and Joey Jalleo, a publicist and director of special projects for The Standard Hotel.

Allying with such organizations as Partners In Health, Solar Electric Light Fund, and charitybuzz, OFD targets the fashion world with an appeal to donate one day’s salary to specific causes. In the past, donations have electrified clinics in Haiti, Rwanda, and Burundi with solar energy.

“OFD came out of James and me going to charity events and being depressed by the messaging and the fact that we never knew where the money was going; it was nebulous,” says Wiedemann. “We have very clear parameters: We want to solar-electrify [a particular] place, with these partners, and it will cost this much.” Their next project, she adds, may well be in the United States. “We’re a small operation. It’s just James and I and a couple of other people. We’re just the ‘woo-hoo’ party, and our partners actually execute the project.”

Wiedemann adds that the fashion industry has responded generously—and she’s not surprised. “People have a love-hate relationship with fashion,” she says. “They misunderstand it, they think it’s incredibly superficial, and they resent you for being involved in it. A friend told me recently, ‘It’s such a catty industry!’ And I said, ‘Tell me, which industry isn’t? Finance, politics, journalism—they’re all catty.”

Wiedemann adds that she is grateful that the industry was “so patient,” allowing her the time to mature into it. She credits her mother, grandmother Flo, and stepmother Thury with helping her along the way. She learned from them that style comes from simplicity, and beauty largely from kindness. “People ask me all the time for a definition of beauty, and I think that’s really it,” she says. “I don’t understand people who are purposefully hurtful and rude and who are fast to play the angry card. I think you have to stand up for yourself, but it’s possible to do that in a kind way.”

“Kindness” is the quality she says she immediately recognized when she met her fiancé, James, at the Raisa Gorbachev Foundation Gala in London five years ago. “Neither of us knew quite why we were there, and we were the dates of people who did,” recalls Wiedemann with a laugh. “Six months later, we ran into each other on the subway, the Number 1 line.” The couple are getting married this summer, probably by taking a subway trip downtown to City Hall (on the aforementioned Number 1 line). “I’m not the bridey-bridey type,” she says.

While Wiedemann has gone far and fast in fashion, she knows that celebrity can turn in an instant. She remembers full well how her grandmother, Ingrid Bergman, went from being a lauded Academy Award-winning actress to a national pariah in the late 1940s after, as a married woman, she fell in love with Rossellini and became pregnant with his child. The United States Congress voted to censure Bergman, effectively kicking her out of the country. “She didn’t deserve any of it,” says her granddaughter. The act was later revoked by Congress in the 1970s.

“You just have to be ready to roll with the punches, whatever life deals to you,” says Wiedemann. “I was sitting in my apartment the other day, and [my dog] Happy was in my lap. I started thinking about how horrible it would be to lose him, and I got so sad. I was squeezing him so tight. And he just looked up at me as if to say, ‘What’s your problem?’”

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