As a schoolgirl back in Kitchener, Ont., Jill Hennessy had her share of growing pains, but she didn't have to endure them alone. "We both wore glasses, and we were both total nerds," recalls her identical twin sister Jacqueline. While other kids were wearing Jordache, Jill and I were wearing polyester that balled up." Then, in high school, the sibs reached 5'7" and turned into swans. "We weren't tall enough to be runway models," says Jacqueline, "but we modeled at shopping malls around Kitchener." Now 33, Jacqueline is a magazine editor in Canada, while Jill blossomed into the star of NBC's Crossing Jordan
, playing a feisty medical examiner. "Jill dresses up so beautifully that the character becomes far too elegant," says the show's creator, Tim Kring. "We have to dress her down so she doesn't look too gorgeous." At the L.A. home she shares with her husband, lawyer-turned-actor Paolo Mastropietro, 37, Hennessy wears little makeup—just powder and Great Lash mascara, "the only thing I've used since I was 17." To relieve stress she makes music. "My guitar is my beauty secret," says the former Law & Order
actress, who once supported herself between jobs by playing that guitar in New York City subway stations. "I think back to when I felt so self-conscious," she says. "To be who I am at this point, that is an achievement."