‘Rizzoli & Isles’ — are they or aren’t they?

The first season of TNT’s crime drama “Rizzoli & Isles” featured an episode with the title “I Kissed a Girl.” Its stars, Angie Harmon and Sasha Alexander, played on a softball team, shared some intimate dinners, drank wine over candlelight and hopped into the same bed for girl talk.

But this is not a gay show.

Series creator Janet Tamaro described Harmon’s Rizzoli and Alexander’s Isles as a “power couple” — the center of a buddy drama, one that broke cable ratings records in its debut run and returns for its second season July 11. But the women are not together, as in together.

Tamaro chalks up the rampant are-they-or-aren’t-they discussion to throwing “two gorgeous actresses together who have great, natural chemistry.” She contends that Harmon’s tomboyish homicide detective and Alexander’s stylish medical examiner “are straight women who don’t fear the interest in or the speculation about their relationship.”

That hasn’t stopped gay pop culture blog AfterEllen from dubbing the show, “totally gay, it just doesn’t know it yet.” Or another lesbian blog, CherryGrrl, from creating a “Rizzoli & Isles” drinking game, advising viewers to take a shot for interaction between the title characters that includes “stares lasting longer than three seconds,” “sleeping in the same bed/couch/squad car,” “adorable bickering which generally relates to sexual tension,” or “complaining to each other about their inability to find a compatible mate, all while being completely compatible mates.” The Washington Post even pointed to a hunky visiting FBI agent as a short-lived distraction from the “faintly lesbian undertones that the show keeps trying to establish.”

Harmon, a veteran of “Law & Order,” said she’s familiar with the online chatter and that it’s “super fun” to play a role that has some same-sex romantic vibes. She’s relishing a character who’s gruff and aggressive, the polar opposite of her own girlie personality, she said.

But as close as they are, Rizzoli and Isles are just best friends, she said. Really.

“I hate to disappoint, but these characters are straight,” Harmon insisted. “If we lose viewers because of it — sorry!”

The show certainly hasn’t been hurting for fans, premiering to more than 9 million viewers last summer. It ranks as basic cable’s most successful series launch ever, drawing a bigger audience than its companion show, the female-led hit cop drama “The Closer.” “Rizzoli & Isles” averaged 8.7 million viewers an episode for the season.

So teasing the audience about the characters’ sexuality, whether a calculated decision or not, appears to be working. Tess Gerritsen, the bestselling author who created Rizzoli and Isles in a series of dark medical thrillers, has written on her own blog that she’s amused by the speculation. Apparently she didn’t have that in mind, but she’s OK with ardent fans and self-proclaimed “Rizzles,” who want to see the women romantically linked.

The series, which borrows from the gritty source novels but lightens them up considerably, divides its time between Rizzoli and Isles’ complicated personal lives and their hard-charging careers. The second season will open with Rizzoli and her younger brother, a beat cop, recovering from being shot in the line of duty. (They were injured in Season 1’s cliffhanger, an armed siege at the police department.)

Rizzoli’s other brother, the black sheep of the family (played by “Something Borrowed’s” Colin Egglesfield), comes home after a stint in jail just after her parents (Lorraine Bracco and Chazz Palminteri) announce they’re splitting up.

Isles, a forensics expert whose big science brain is covered in an always-perfect coif, will deal with her own fractured family, a bit of baby fever and a past love dropping in to mess with her equilibrium. (Neither character seems to have much luck with men. Conveniently.)

The two will work on — and solve, within 40-some minutes — murders at Civil War reenactments, fertility clinics and pro baseball camps. They’ll deal with a modern-day Salem witch hunt, a military car bombing and a prolific serial killer. Guest stars will include Jacqueline Bisset, Bill O’Reilly (as a murder suspect!), Richard Thomas and Chris Vance.

The producers and stars said the “Cagney & Lacey” comparisons were somewhat inevitable, though Tamaro said she sees the title characters more as “Kirk and Spock.” Alexander, an “NCIS” alum, said she thinks the show breaks old TV tropes.

“Women in the workplace are often portrayed as catty and competitive, and it’s rare that you get to see them as smart friends and colleagues who can debate and disagree,” Alexander said. “They don’t have to always sabotage each other and fall for the same guy.”

Or, any guy at all?

calendar@latimes.com