NCIS

Pauley Perrette's lab rat Abby has been let loose in the NCIS squad room. In a scene she's shooting for a big two-part episode airing November 16 and 23, she's trying to play pin the tail on the bomber. Pointing to a video of a suspect playing on a computer screen, she blurts out to Sean Murray's McGee, "He just confessed he knew how to make the murder weapon! I mean, how many people know how to make a homemade Claymore mine?"

"In this room?" asks McGee. A couple of visiting Israeli agents raise their hands. So does Cote de Pabl, as NCIS team member Ziva David. Then, sheepishly, so does Abby herself. "OK, fine," she mutters, reluctantly withdrawing her point.

Perrette and de Pablo may be easy on the eyes, but they can be hard-asses, too. In a medium where many actresses are still relegated to subordinate roles, you'll find no such complaints about NCIS. Ziva is the team's deadliest member, and Abby is smarter than all of her counterparts. They're not just action-show glamazons, either, but arguably the two most eccentric characters on an already deeply quirky series. The men on the show are cleverly perfected variations on the strong and silent type, the tech whiz or the wisecracking boy-next-door. Meanwhile, you'd have to venture a lot farther than next door to find a crack Israeli assassin who looks stunning in Gucci, or a genius-level forensic scientist with a spider-web tattoo and pigtails.

Together, they're a veritable Claymore mine of female stock-character demolition. "There aren't a lot of roles like this around for women, and we have two of them," crows Mark Harmon, who stars as squad leader Leroy Jethro Gibbs. Abby is not just the brainiac of the show, but also its sweetest, most open-hearted character. Still, Harmon says, "Abby's plenty tough. And Cote's a dancer and a kickboxer, for real. She moves well, so she can put an instep on your chin and look beautiful doing it."

This month, the women of NCIS are stepping it up. Ziva plays a prominent part in the next three episodes. On November 9, she goes undercover with Robert Wagner, who returns to charm her as Tony DiNozzo's slightly shady dad. Then, her own extremely estranged Mossad-chief father (Michael Nouri) resurfaces for the two-parter. These Ziva showcases follow on the heels of an Abby-centric episode, "Cracked," which Perrette describes as the hardest script she's had in the show's eight-season history, just for the sheer number of monologues.

And expository monologues are Abby's stock-in-trade. As Perrette says, "It's usually 'Whadda ya got, Abbs?' and then I talk for a page. And then 'Where?' and I talk for a page. 'How?' and I talk for a page. And then 'Thanks, Abbs!'"

Even though Abby's role in a typical episode consists of just a couple of jargon-heavy scenes down in the lab, she may be the most beloved character on TV's No. 1 scripted series. That theory was borne out when the Q favorability ratings released earlier this year revealed a three-way tie for the most liked celebrity in America, between Tom Hanks, Morgan Freeman and Perrette — the only woman to even make the Top 10

How did she become America's sweetheart with such relatively limited exposure? "We are often told, 'Leave the audience wanting more,' and we definitely do that with Abby," says exec producer Shane Brennan. "If you ask the audience to start remembering classic scenes, a lot of them are Abby moments — and because she's not on the screen as often, we go out of our way as writers to create those wonderful moments."

They're not always in the script. If there's not a lot of quirky character stuff on the page, "Mark and I can create something — just a look between the characters, or some funny physical thing," says Perrette. "My job is to take all these long lines and not only memorize and spit them out, but do it 100 times faster, because she's a caffeine addict. And make it funny. Michael Weatherly [Tony] and I pinky-shook, when the show was starting, that we'd make every episode as funny as possible. That's what's so fun, figuring out how to get the comedy into the drama."

A dedicated social activist who finally overcame her Twitter aversion to promote her favorite charities, Perrette is involved with about 30 causes off screen, from homeless shelters to gay rights to animal rescue. The last may be the most apt, because Perrette's role model and acting coach is...her dog, Cece.

"I actually play my rat terrier-Chihuahua mix on the show," she reveals. "I have played her since Day 1. I don't stand like Abby. I'm very slouchy. Everything Abby does is based on my dog — the way she cocks her head, the way she interacts when she's confused or excited. And her ears are Abby's ponytails."

But the character's puppyish displays of affection? That's Perrette, not the pooch: "Abby hugging everybody — it's because my family's from Alabama, where we hug everybody," she says. Abby is "the big heart of the show. She's sensitive and loves people and cries and misses them and gets her feelings hurt. There's a big Abby heart on her sleeve — probably both sleeves, plus her chest, her jacket, her backpack...."