Sasha Alexander Sasha Alexander

What's a medical examiner to wear to a crime scene? 

If you're Rizzoli & Isles' Maura Isles, you throw on some Balenciaga and Bottega Veneta.

"Obviously!" Sasha Alexander, who plays Isles on the new TNT series (Monday at 10/9c), tells "Don't they all wear that? It's pretty fantastic. I'm not complaining. She has great clothes and she has great taste. We are referring to her as Carrie Bradshaw with a dead body."

Though Isles is more often among the dead than living, the fashionista does have a close — though very different — friend with a pulse: Detective Jane Rizzoli (Angie Harmon), with whom she teams up to solve Boston's grisliest crimes.

Check out photos from Rizzoli & Isles

While the quirky and icy cool Isles dresses in designer duds, awkward tomboy Rizzoli prefers T-shirts and jeans ("Maura definitely gives Jane a few lessons on 'You can't wear that'"). Isles comes from money; Rizzoli's blue-collar clan includes her overprotective mother (Lorraine Bracco

) and a patrolman-brother (Jordan Bridges)."It's kind of, like, 'Opposites attract to kick a--.' You don't see two lead female [crimefighters] on shows a lot," says Alexander, 37. "I like their relationship because they have a different sense of style, backgrounds and points of view, but there's a true female friendship. It's not the kind where these girls grew up together and they're besties. They're adult women, doing separate jobs who met on the job, but making their lives work. I love that it's genuine and there's no cattiness that you sometimes see elsewhere."That may be attributed to the fact that the series — which premieres after TNT's other girl-power drama The Closer — was created by women from the ground up. The show is based on the successful book series by physician-turned-writer Tess Gerritsen and adapted by Janet Tamaro (Trauma). "They get it. They're not trying to stereotype it. [Rizzoli and Isles] both go from vulnerable to sexy to smart to angry," says Alexander, whose crime procedural resume includes NCIS. "That's the best part about getting to play her. You can call a female producer and say, 'Oh, c'mon! They wouldn't be fighting over this guy! Not all girls want to date the same guy.'"

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That doesn't mean Rizzoli and Isles always get along. The worldly Isles tries — to varying degrees of success — to get her pal to date and "open her mind," while Rizzoli gets irked by Isles' eccentricities. "Maura's very mathematical and clinical. She won't call blood 'blood' unless it's gone to the lab. She'll call it a 'reddish-brown stain,' and that's really frustrating because Jane's impatient and wants answers," Alexander says. "At the end of the day, I think they have a tremendous respect for each other and that allows them to be close."Though the pilot partially draws from Gerritsen's first book, The Surgeon — named for the serial killer who once nearly killed Rizzoli — Alexander says the show will deviate from the novels in subsequent episodes. "[A show] needs more crime than the books have and more storylines," says the actress, who did not read the books until she got the part. "I have no idea what direction we'll go except that we'll continue to explore their relationship and their pasts. There's an episode coming up about my father who comes back. I don't know anything else yet, but the funny thing would be if he shows up with no sense of style!"So will clotheshorse Isles ever dress down, or will Rizzoli ever dress up?"On the job? I don't think so," Alexander says. "Jane [fights] a lot of the bad guys. She protects me since she's in the right shoes. I don't want to break a heel!"