Chloë Sevigny claims she'd been up until 4:30 a.m. Unsurprisingly, she doesn't look like it: no dark circles, impeccable mascara. Her hair is pulled into a streamlined ponytail, and she pushes back her couture leather jacket to reveal a black halter top. "Your penmanship, it's very cute." Let this be said: she knows how to win over an interviewer.

Not that she needed to. In this writer's opinion, Sevigny is – along with the little-known one-monikered Ryo – the most interesting female screen presence of her generation. Her personally honed look in each film is a major factor; unlike most peers, she brings an auteurist approach to costume that matches the sensibility of the directors she's selected (another auteurlike stroke). In Olivier Assayas's new Demonlover, Sevigny's character sports a yé-yé girl hairstyle (a bit like Chantal Goya's in Godard's Masculin, feminin) and billowy '70s office wear that's slightly off. "The costume designer wanted me to be a techno Euro girl," she says. "I thought my character should try to look corporate but get it wrong. Her heels should be too high, her skirts too long – slightly bad style."

Minutes into Demonlover, one character injects a pudding cup-size airplane package of Evian water with a sedative in order to drug a coworker; it's the first of many fetish-y triple crosses in Assayas's thriller, a mazelike Valley of the Cyberporn Corporation Dolls navigated by Sevigny, Connie Nielsen, and Gina Gershon (who exhales cigarette smoke with a well-timed precision that would make Susan Hayward proud). Needless to say, Demonlover has camp to spare. Assayas and cinematographer Denis Lenoir aim their critical vision at contemporary life's glossy-glassy illusions and mirror images; one character's split-second TV glimpse of Kiyoshi Kurosawa's Pulse aligns Demonlover with that premonitory film's computer nightmares. Assayas's dystopian view of surveillance culture presents the Internet as a toxic technological portal. "I took the part because I love Olivier's films, especially Irma Vep," Sevigny says. "I think he does interesting things with women in his movies, and that's hard to find. And I wanted to speak French. I thought it would give me something to hide behind if people thought I was bad."

The experience brought its share of frustrations. "I had to learn French phonetically, and I studied for three months before shooting," she explains. "Then when they cast Connie Nielsen – her English sounds American, though she's Danish – they said it wouldn't make sense for me to speak French in my scenes with her. So half of the French dialogue I'd labored over was out the window." Demonlover also gave Sevigny a crash course in the differences between French and U.S. on-set practices: "When we were filming in Mexico, September 11 happened, and that morning they still made us work – in a helicopter. They're very diligent; they have strict work ethics."

Two other recent Sevigny projects, Lars von Trier's Dogville and Vincent Gallo's The Brown Bunny, are also overtly auteur-driven. "Olivier gave me the least amount of direction," Sevigny says when asked to compare the three directors' approaches. "He speaks better English than I do, so it wasn't any sort of communication problem. He just let me do my own thing – which is kind of scarier. Lars is loose, as well. He liked me a lot, I think, because I'm not an overactor. He didn't have to tell me to take it down, which was his main direction with everybody. Vincent made me do things over and over again. He's a control freak. To me, it was more of an exciting challenge, because I was fighting with him and the part."

There are some upcoming brouhaha'ed movies that don't star Sevigny, and she's looking forward to viewing one in particular: "I'm excited to see The Passion, the Mel Gibson movie. He's such a freak!" When I observe that Gibson seems to have entered a Whitney Houston phase, revealing a newer, truer face, she agrees, adding, "I hope I have one of those phases." Among recent trips to the cinema, Peter Mullan's The Magdalene Sisters stands out. "I'm Catholic, and I still loved it," Sevigny says. In terms of music, her current fave is the reaper-worshipping Finnish metal group Children of Bodom.

A few years ago In Style asked Sevigny to select a film-star role model. Her pick: Mia Farrow. "I chose Mia just because of what she's done with the children," she says. "I think it's so honorable. And I got to go to the house and see the way she interacted with them." Farrow isn't Sevigny's only role model, though: "I think Sissy Spacek has the best career. I also love the kooky girls – Shelley Duvall and Sandy Dennis. But when you think about what was nominated for an Oscar in any given year during the '60s and '70s and compare it to what's out today – how could we ever compete?" Perhaps it's hard to determine the overall quality of current films when so many are being made, I suggest. "Yeah, I guess," she says doubtfully. "I'm disappointed in filmmakers."

As for Sevigny's next project, she'll be featured in Woody Allen's yet-to-be-filmed new project. What would Mia think? (Johnny Ray Houston)