She has slowed down some now that she has settled into her role as Kate Warner, an L.A. lawyer who suspects her sister is unwittingly engaged to a terrorist. "Sarah's quick to joke and tease you," says costar Elisha Cuthbert (the ever-imperiled Kim Bauer). Plus, "she's so fashionable! She gives me tons of advice about clothes."
"I used to borrow clothes from my mom's closet," says Wynter, 31, who started play-acting as a toddler in Newcastle, Australia. The oldest of three children of a physician father (who died when she was 13) and a mother in the federal judiciary, she knew by the time she graduated from boarding school in 1988 that she wanted to make it as an actress in America. After more than 10 years of minor roles, she got cast in Lost Souls and The 6th Day, where she worked out during lunch breaks with Arnold Schwarzenegger ("I was like, 'Can you believe this? Arnold is showing me a bicep curl!' ").
Now she lives with her fiancé, screenwriter and actor Emmanuel Xuereb, 37, in a Hollywood Hills home. "Eventually we want kids, but 24 takes place in one day, so you can't write a pregnancy in," says Wynter. "I'll be menopausal and the producers will be like, 'Okay, the show is off the air, now you can have kids.' "