Standing in her cozy west Los Angeles kitchen, actress Jill Hennessy whispers in italiano to her husband, Paolo Mastropietro. "You know, she spoke not a word of Italian when I met her," says Mastropietro, the Bronx-born son of Italian immigrants. "I taught her the language, and now she speaks it better than I do. She's really a Renaissance woman."

"Dude," interrupts Hennessy, "you are the Renaissance man."

Therein lies the Jill Hennessy paradox: Part sultry beauty, part slang-slinging slacker, "she's like Catherine Zeta-Jones meets the surfer from Fast Times at Ridgemont High," says Miguel Ferrer, Hennessy's costar on the new NBC hit Crossing Jordan. "She acts in a way you don't really expect a gorgeous woman to act."

Make that a gorgeous woman with a steel stomach. To research her Jordan role as crime-solving medical examiner Jordan Cavanaugh, Hennessy spent a week observing coroners on the job at the Los Angeles county morgue. "The smell is the most disturbing thing," she says. "But I didn't faint or get sick or anything like that. It was fascinating."

Those real-life pathologists might take issue with her character's contempt for a lab coat—think instead snug leather pants and itty-bitty denim jackets. The clothes, like the sprinkling of the word "babe" in Jordan's scripts, reflect the influence of the show's 33-year-old star. Compared to her mid-' 90s stint as buttoned-up assistant district attorney Claire Kincaid on NBC's Law & Order, "this role is much closer to who Jill really is," says Jacqueline Hennessy, the actress's identical twin sister. Adds Tim Kring, Jordan's creator: "Jordan is Jill. She's brassy, a real broad." And don't forget bawdy, says Ferrer, 46, who plays Hennessy's boss on the show. "We laugh until we're nauseous."

When she's not making naughty suggestions about various uses for medical props, Hennessy often can be found singing and strumming a guitar in her trailer. "I call her the Human Jukebox," says Benjamin Bratt, a close friend since the pair costarred on Law & Order. "Almost any pop song you can throw at her, she can improvise. She does an amazing Indigo Girls and a better Springsteen."

Hennessy began compiling her repertoire at age 22 in New York City, where as an aspiring actress she supported herself by singing on city streets and in subway stations. "I'd put the guitar case out for people to throw money into," she recalls. "I sang Springsteen, Judy Collins, U2—it was great."

Her primary influence was her father, John, 55, a meat importer and exporter in Ontario, Canada, where Hennessy grew up. "My father would come home after a week of traveling, and we would sit on the kitchen floor and he'd sing with us," she recalls. When Hennessy was 12, her parents divorced, and her mother, Maxine, now 53 and a legal secretary, moved out; the siblings—Jacqueline, Jill and brother John, now 27 and a freestyle BMX bike rider and restaurant manager—remained with their father. Although they still visited their mother, who lived nearby, regularly, "it was tough when she left," says Hennessy. "We were much closer as siblings because we had to rely on each other so much."

The twins, known as Jacq and Jill, grew even tighter when both began modeling and studying acting and music. While Jacq later found she preferred writing—she is now an editor at the Canadian women's magazine Châtelaine—Jill, dazzled with performing, graduated from Grand River Collegiate, a public high school in Kitchener, Ont. , and headed for Manhattan.

A series of minor acting roles followed, along with the twins' brief appearance in the 1988 big-screen chiller Dead Ringers, but Hennessy's breakthrough didn't come until she landed on the New York City-based Law & Order in 1993. One year later she met Mastropietro, 37, who was then working as a bartender in Greenwich Village after giving up his law career to become an actor. Says Hennessy: "I went up to the bar and ordered two rum punches, and that was it." In October 2000 the couple eloped to Cantalice, a tiny town in Italy; they married again in Manhattan last January in a family-only ceremony at city hall with Mayor Rudy Giuliani officiating. "The mayor gave a beautiful speech," recalls Mastropietro. "It was cool."

In addition to her skills as a linguist—besides Italian, she speaks French fluently and "enough German to get along"—Hennessy is an avid motorcyclist who frequently accompanies her husband on trips in and around Los Angeles, where the admittedly homesick couple moved in July from New York City when Jordan began filming.

Biking isn't the pair's only passion. A shared love of cooking led them to open Hennessy's Tavern in Northvale, N.J., in 1999. "We serve comfort food like chicken pot pie and all sorts of burgers," says Hennessy, who admits to a childhood dream of making her living in the kitchen. "My sister and I always thought we'd be bakers. We started with shortbread, thinking since it only had three ingredients, it had to be easy. To this day we make really good shortbread."

Michelle Tauber
Pamela Warrick in Los Angeles

  • Contributors:
  • Pamela Warrick.