The words "Rescue Me" would have had an entirely different meaning for Diane Farr if she'd auditioned for Desperate Housewives. "I told my agent, 'No, I'd really be terrified to be with that many actresses at once,'" Farr says. "Boys are so much easier."

Denis Leary and his fellow firemen may dominate FX's dramedy, but their female costars rival the ladies of Wisteria Lane for sheer fierceness. In addition to Farr, who plays Laura, the fire crew's sole distaff member, three other actresses have major roles this season: Callie Thorne as 9/11 widow Sheila, who's expecting a baby with Leary's Tommy Gavin, her late husband's cousin; Andrea Roth as Tommy's ex-wife Janet, who's run off with their children; and Ashlie Atkinson as Theresa, a self-confident, sexy, plus-size woman carrying on a torrid affair with FDNY hottie Mike, aka "the Probie" (Michael Lombardi). "These women have depth," says Thorne, a veteran of Homicide: Life on the Street and The Wire. "We're not just blowup dolls."

Cocreators Leary and Peter Tolan started fleshing out the females after being shocked by the number of women who tuned in to the raunchy boys-club antics on Rescue Me last summer. "For women, the idea of a sexy fireman is a fantasy," Roth says. "They're these strong, manly men rescuing you."

But that's not the only thing attracting female viewers. "Women may start to watch because it's eye candy," says Atkinson, who recently starred in Neil LaBute's award-winning off-Broadway play Fat Pig. "Then the story lines and character development and complexity of the relationships really get them."

This season's story lines will definitely heat up for the actresses. Among the developments: Sheila frantically tries to keep Tommy, but he reunites with Janet. The romance between Theresa and Mike takes a dark turn, and Laura breaks FDNY code by hooking up with fellow firefighter Franco (Daniel Sunjata).

And, in Farr's case at least, the action has proven to be as demanding physically as emotionally. "I have to carry 65 lbs. of gear," she says. "I only weigh about a buck-twenty-five, so that's over half my body weight. I was in acupuncture and seeing a chiropractor twice a week while we were shooting."

Now the show's other women want to get in on some action. "Yeah, man, I'd love to have a big, old-school, hair-pulling catfight with Andrea," Thorne says. "That would be such a gas." Maybe she should have auditioned for Desperate Housewives.