Unlike most us, Sarah Michelle Gellar already knows exactly how she plans to ring in the millennium. "I'll be in Australia with a group of friends," she says excitedly over lunch at a sun-drenched L.A. pasta place. "We're going to start at the Great Barrier Reef and work our way down the Gold Coast, scuba dive and go to the rain forest." She looks down over her sunglasses and serves up a playful smirk. "You didn't expect me to have an answer for that one, did you?"

Not really, but then again, anyone who has managed to get where Gellar is at the ripe age of 22, must be something of a go-getter. Not only is she the star of her own TV series, the increasingly popular and ever-surprising Buffy the Vampire Slayer, but her movie career is in high gear as well thanks to hits like Scream 2 and Cruel Intentions. She's also just signed to be a spokesperson for Mabelline, ironic considering that today, she's sporting jeans, braids and nary a stitch of makeup. "At least I have on two rubber bands that match," she boasts, gesturing to her girlish pig-tails. "I had a pink and a green one on this morning."

Gellar's journey to this glamorous life got its start in a Manhattan restaurant where she was discovered by a talent agent when she was just 4 years old. Her first job, a TV movie called Invasion of Privacy, came a week later and was followed by a whole slew of commercials, most notoriously, a Burger King spot which made history by being the first ad to deride a competitor by name. "The only part of it that I understood," Gellar says referring to the resulting lawsuits, "was how come all my friends were having their birthday parties at McDonald's and I couldn't go?"

Providing a shoulder to cry on at the time, and ever since, was Gellar's mother, Rosellen, a former teacher, who raised Sarah on her own in an apartment on Manhattan's Upper East Side. "Everything I am is because of my mom," Gellar says of the woman who shuttled her between auditions, jobs and school. "She's so cute too. She still cuts out little articles from like local papers and brings them to me. "Gellar is much less effusive about her father, who divorced her mother when Sarah was 7, describing him as "non-existent" in her life. Pressed to say a little more about him, she opts to quote a line Keanu Reeves used in Parenthood: "You need a license to go fishing, you need a license to drive, but any butt-reaming asshole can be a father."

So it was the Gellar women against the world and they were winning, with more jobs to come for Sarah including the role of teenage Jacqueline Bouvier in the miniseries A Woman Named Jackie. "That job meant a lot because I'm psycho-obsessed about JFK, Jr.," Gellar confesses, adding that George founder is welcome anytime to come play her love interest on Buffy, assuming Joseph Fiennes doesn't jump at the offer first. "My mother was a teacher at the church that Jackie worshipped at, and once a year Caroline, John, Jr. and Jackie would go there and I would take off that morning from school just so I could see John, Jr. He's so beautiful."

Back then, Gellar was as much a firecracker of determination as she is now. Still, balancing her career, school and a social life wasn't always easy. In seventh grade, when most pre-teens are bugging their parents for more allowance money, Sarah suffered what she calls her "biggest devastation" when the play that was to be her Broadway debut, Neil Simon's Jake's Women, closed before it even made it to New York, and when she returned to her school, friends, nobody would talk to her. High school was a better experience for Gellar once she settled on the right one."I started out at La Guardia," she explains referring to the Manhattan-based school of the arts, "and I hated that school. I got beat up pretty much every day and the education wasn't that good. I left and went to Professional Children's School which I loved. "An over-achiever even then, Gellar was a straight-A student, but that didn't keep her from having fun. "Making out in parks is a very big thing to do in high school when you grow up in New York City," she reveals. "There was a playground right near my house and the swings saw a lot of action from me." Not that she wasn't getting plenty of action on-screen at about the same time, playing the conniving Kendall Hart on the daytime soap All My Children. "That was definitely head-trippy," she recalls, referring to the fact that Kendall was seven years older than she was, "to be 16 and have these love scenes with a man old enough to be my father. I mean, I was married twice and I hadn't even graduated high school yet."

Amid rumors that she clashed with her TV mom Susan Lucci, Gellar left All My Children to pursue bigger and better things in Hollywood, but even with a daytime Emmy under her arm, the doors didn't exactly fly open. "It was like starting from scratch again," explains Gellar who promised her mother that if she didn't find work within a year, she'd start applying to colleges. "You can be very, very famous in the soap world, then you go into the real world, as I say, and nobody knows who you are. Up until the day I got Buffy I was still getting from casting directors, 'Oh, she's not ready, she's too green, she's too soap.'"

Though now it's impossible to even imagine anyone else as Buffy, at the time, Gellar had to jump through hoops too land the part, auditioning more times than she can remember. "On my last audition I went in and tested and came out and they said, 'We need you to read one more time,' and I just started to cry," Gellar recalls. "I said, 'I can't do this. You guys are wrecking me. I lived and breathed this for two weeks. I can't do it anymore. I don't have it in me.' Then the casting director basically dragged me back in and everybody started laughing and said, 'Congratulations, you got the role.' Meanwhile, I was still crying and sniveling."

As any fan can tell you, the role was a perfect fit. "Buffy 's very similar to me when I was growing up," Gellar says, "a child in an adult world, sort of trapped between the two. Does Buffy go to the prom or does she save the world from demons? My life was similar; do I go to the slumber party or do I go to my audition?" The show also gives Gellar, who's studied Tae Kwon Do for four years, a chance to kick a little ass. So how much of Buffy's derring-do is actually her? "I do as much as I can," she says. "My stunt double, Sofia, has a better butt than I do, so I prefer that if they're going to do butt shots, that they use Sofia." Gellar breaks into giggles, then adds, "She's my trainer now though, so I am going to look just like her soon."

In addition to keeping her fit, on time with her house payments, and on the cover of magazines, Gellar's success on Buffy has also been her ticket into movie roles. Her track record, thus far, is heavier on hits than misses, though she got brutally offed in both her '97 releases: Scream 2 and I Know What You Did Last Summer. "Jennifer Love Hewitt and I like to refer to that as I Know What Your Breasts Did Last Summer," she says, joking about the fact that she and her co-star spent most of the movie bounding about in skimpy tank tops. "Here's a funny story: I hated the fried food in North Carolina where we shot so I barely ate and I lost an entire cup size in my breasts. At the end of the movie I had to match a shot from the beginning, and I had to wear these silicone, squishy thingies, all pushed in and taped, because I didn't match."

Gellar did without the squishy thingies in her two '99 releases, though the first, the romantic comedy Simply Irresistible, could have used a squishy thingy or two. It seemed to vanish from multiplexes as soon as it arrived. "Before this movie I never really understood how great actors made bad movies," Gellar says reflectively. "I thought, 'Didn't they read the script?' and then you realize that it's not just a script, it's not just actors. Sometimes, things get lost in the translation and it can destroy a movie."

She fared much better in Cruel Intentions, the shockingly naughty teenage reworking of Dangerous Liaisons, in which Gellar turned her Buffy image on its head, playing a coke-snorting, she-devil named Kathryn who promises her studly stepbrother that if he succeeds in deflowering the new virgin in town she'll let him "put it anywhere." "I think it was important that I did that part," Gellar laughs, when asked if she was worried about how her sex-starved character would sit with Buffy lovers. "Everyone has to remember that I'm an actress. If you wait too long (to branch out) people can forget that you do other things, and they won't accept you. "Gellar says she got the inspiration to play Kathryn from her own junior high school experience in Manhattan, where almost all of the kids had far more money and far less supervision than she. "I remember all the girls wore these Betsey Johnson dresses," she recalls, "and I couldn't afford them new and so I always bought last season's in the $5 bins. When I got All My Children, I went out and I bought two dresses from the brand new section and I was so excited."

Cruel Intentions also served up Gellar's first girl-on-girl kiss, with Zoe, Duncan, Jack and Jane star Selma Blair. "I kept thinking, 'I have had to kiss guys that I don't want to kiss. At least Selma is a friend and I know where she's been'," laughs Gellar. "Afterwards, Selma said, 'I was nervous that you would think I was a bad kisser.' I said, 'You weren't nervous about the kiss itself?' She said, 'No. I was just afraid that you'd think I suck.'" As for the upside of doing kissing scenes with girlfriends, Gellar can sum it up in three words: No beard burn. Gellar hasn't decided yet what she's going to do for a big screen encore. "When I read Cruel Intentions, it just jumped off the page," she says, "and I've learned that you need to wait for that feeling."

As for her off-screen love scenes, Gellar says she's doing her share of dating but isn't about to settle down. "People say, 'Why aren't you in a serious relationship?'" she scoffs. "Hey, I'm 21 years old. This is my time to have fun." She's notoriously tight-lipped about the identity of her mystery dates (she's been seen at premieres with...) explaining that she learned from watching the stars that came before her, like Gwyneth Paltrow and Sandra Bullock, whom she calls her role model, that it's better not to kiss and tell in Hollywood. Though she claims she's not much of a schemer when it comes to romance, Gellar has been known to create a little mystery by telling her would-be suitor that the flowers on her table are from "a friend" when they're actually from her agent. And she will admit to getting romantic with fellow actors though she says it's not her ideal situation. "I have a tendency to gravitate toward people that aren't in the business," she says, "and it's hard now because I don't really meet that many people that aren't in the business."

She did meet a new gym buddy recently, though: Shaquille O'Neill. "He's my workout boyfriend," she says proudly. "He spots me every once in a while." And what words of encouragement does the basketball superstar offer when Buffy's pumping iron, Go for the burn? Pump it up? "He says, 'That's it?'" Gellar says then bursts into laughter.

Shaq would be smart to stay in good with Gellar, for she's fiercely loyal to her pals. She's had the same best friends, Ashley and Brittany, since she was in elementary school and believes that she's most herself when she's around them. "One of my best friends and I drove down to the set of Angel last night to surprise David," she says referring to the Buffy spin-off series starring her former love interest, David Boreanz. "When I'm with my friends, we're like teenagers, just really giddy and silly. Well, the executive producer of Buffy was there and he said, 'I've never seen you like this. It is so endearing'."

Seth Green, who plays Oz on Buffy, says he's seen plenty of Gellar's endearing side. When the two went to the premiere of Spiceworld as part of a group, Green had just split from his long-time girlfriend. "I showed up at Sarah's place," he recalls, "and she said, 'Where's your girlfriend?' and I said, 'I don't know.' Sarah didn't say anything, didn't ask anything, she just knew and she took my hand and said, 'Well, I'll be your date tonight,' and literally didn't leave my side the entire night." Asked what she remembers most about the evening, Gellar leans forward in her chair and whispers, "Ginger Spice literally felt Seth up."

Though watching Ginger Spice cop a feel off her friend wasn't the social highlight of Sarah's year, it might have been close. "If anything I've become more of a homebody lately," admits Gellar. She's not alone, for it seems that many of her peers, like Jennifer Love Hewitt and Melissa Joan Hart, are also squeaky clean show biz veterans who have worked their entire life to get where they are, and are not about to jeopardize it with some Shannen Doherty-style bad behavior. "I think Hollywood's giving the success to the people that can handle it," figures Gellar, who missed the New York premier of Cruel Intentions because she was needed at Buffy. "There's a lot of sacrifice, and hard work comes with it."

Still, the woman who bounces of the walls every week on Buffy leaving dead demons in her wake must be itching to cut loose. "Actually, I was supposed to go to the Hole-Marilyn Manson concert tonight with the girls from Buffy," she teases, "but I have an early call tomorrow and some big meetings after work so I'm going to go home and go to sleep."

Well, there's always Australia.