TV

Actress Sarah Shahi has rock n’ roll in her heart

Playfully resting her Chanel boot on the banister of the ornate, sweeping staircase inside a bustling Manhattan hotel, Sarah Shahi tosses back her head and gives a sexy, throaty laugh.

Actually, it’s more of a snort. The beautiful TV star, who was born Aahoo Jahansouzshahi and is descended from one of the first ruling shahs of Iran, is the picture of glamour and sophistication. But beneath the cool exterior, this down-to-earth Texan is enjoying the elements of farce.

A group of onlookers — pharmaceutical reps attending a conference — watch The Post’s photo shoot, enthralled. Now and again, a random guest ascends the stairs, blissfully unaware that they’re sabotaging the shot. Shahi shifts her leg to let them through, like some shapely drawbridge.

“Hi,” she says, as another interloper sidles past. She pulls a face of mock-frustration for the camera, as if to add: “No rush, we’ve got all day!”

It’s a lighthearted moment that Sameen Shaw, the tightly wound character played by Shahi in the hit CBS crime series “Person of Interest,” would be unlikely to appreciate. The emotionally detached former government assassin rarely has time for levity.

“She is incredibly hard,” says Shahi, who is currently filming the third season of the show on location in New York City. “If Jason Bourne and Catwoman had a baby, Shaw would definitely be it.”

The cold-blooded killer has knocked off various shady types with a bullet between the eyes. So it’s fun for the woman behind the role to show her feminine side for a photo session, even if she does insist a pretty Monique Lhuillier gown be paired with her own S&M-style Chanel boots, covered in zippers and chains.

“The more contradictions I can find in my clothing, the more attracted I am to it,” says the 34-year-old actress, a former Dallas Cowboys cheerleader whose style inspirations include Kate Moss and Winona Ryder, pioneers of the thrown-together “anti-fashion” look of the 1990s.

“I love anything I can wear with either Keds or cowboy boots and a beaten-up motorcycle jacket,” adds Shahi, who has numerous tattoos, including her mom’s signature on her arm. “Anything soft that you can add a bit of hard to, and vice versa,” she says.

Most of the time, however, she dresses for practicality. Shahi flies back and forth as often as she can between her home base of Los Angeles (where her husband, “Shameless” actor Steve Howey, 36, lives with their 4-year-old son, William Wolf) and Brooklyn, where she is renting an apartment in Williamsburg until “Person of Interest” wraps in April.

Filming takes place five or six days a week, with call times usually between 6 a.m. and 9 a.m. Shahi rarely leaves the set until late in the evening.

“In the morning, I go right into hair and makeup, I have a protein-packed breakfast with sausages, bacon, sautéed avocados, onions and mushrooms, and then I start [filming],” she explains. “Then I get home, study my lines, take a shower and repeat the process all over again the next day.”

Not that Shahi is complaining. “I am loving it,” she says. “The character is fantastic to play. She is so cool. I don’t think I could ever be [exactly] like her, but she taps into different parts of my personality.”

In recent weeks, the tough-girl character suffered the indignity of posing as a yoga instructor to trap a potential criminal through a dating site. It’s a running joke that Shaw only gets along with the team’s dog, Bear. Forget socializing and schmoozing: Shaw prefers to work on her fighting technique before shooting at people’s kneecaps with a Glock 36.

Actress Sarah ShahiTamara Beckwith

“It’s pretty fun,” says Shahi, who first took up martial arts in her native Euless, Texas, as a teen before performing musical theater at Southern Methodist University and auditioning to become a cheerleader with the Cowboys.

A keen markswoman in real life (she owns a 9mm gun), Shahi does most of her own stunts. “It’s the reason I said ‘yes’ to the show,” she says. “I’m somebody who is not afraid. I don’t have a fear of heights, so the higher up they can dangle me from that building, the better off I am!”

The only downside to starring in a successful prime-time show filmed on the East Coast is living so far away from her family. “I miss my son, terribly,” Shahi admits. But they keep in touch every day via FaceTime and, since “Shameless” is filmed largely in LA, Wolf is enjoying plenty of daddy time with Howey.

The couple started dating more than a decade ago, after working together on the set of “Reba,” on which Shahi was a guest star and Howey had a regular role. “It was kind of full-on from the moment we met,” she recalls. “I don’t think I could be married to someone who wasn’t in this business.

“We talk about how our days went over the phone and we understand exactly what it’s like.”

Before the pair wed in February 2009, Shahi spent two years in Vancouver filming the Showtime lesbian drama “The L Word.” Her character, Carmen, became a fan favorite with plenty of girl-on-girl nude scenes — which, Shahi says, Howey was OK with.

“I still have quite a few followers from ‘The L Word’ who I adore,” laughs the actress. “And yes, sometimes I do get hit on. I still enjoy it. I hope I’m 92 years old and still getting hit on.

“It’s nice when you get appreciated by either sex, whether it’s male or female. It’s validation. I wear a wedding ring, but if someone wants to tell me I have some good qualities, I’ll listen!”

As for where those qualities come from, she says, “All I can say is that, if there is anything good about me, I got it from my mom.” A Spanish-born interior designer, Shahi’s mother, Mahmonir, raised the actress and her two siblings after their dad walked out on them.

Shahi no longer has a relationship with her father, who fled Iran in 1978, a year before that country’s revolution, because members of his once-powerful family were allegedly on a hit list.

“I had a superwoman for a mom,” explains Shahi. “[My dad] never gave us a penny, but [my mom] did everything she could to make us feel like we had everything we wanted.”

It was her mother who supported Shahi’s decision to quit college during her sophomore year in 2000 to pursue her dream of becoming an actress. Soon after, the director Robert Altman came to Dallas and cast her as an extra in his movie “Dr. T and the Women.” He immediately spotted her talent and encouraged her to move to Tinseltown.

“Mom drove me out west to Hollywood in my cherry-red pickup truck,” recalls Shahi. “She dropped me off, and I never looked back.”

When she first met Altman, she hadn’t quite realized how accomplished and famous he was. But, as soon as she arrived in LA, she heard his name mentioned everywhere. “I felt intimidated,” she says. “He’d given me his contact details, but I never felt comfortable about calling him because I’d built him up so much in my mind.”

Instead, she got an agent and a manager within her first week and started to land jobs on film and TV. That work led to more substantial, regular roles, such as parts in “Teachers,” “Alias,” “The L Word” and “Fairly Legal.”

“It’s been quite a ride,” says Shahi, who laughingly describes her career choice as “professional make-believe.”

But there is one drawback: commitment.

Shahi insists that, were it not for her chic TV role, she would shave her head.

“That’s something I have to do every day — talk myself away from the razors,” she says with a giggle. Once her life is no longer dictated by the show, she may look quite different. “First off, I’m going to chop it off, bleach it white and have Jet Black eyebrows. Then, when I’m done with that, I’m going to shave it. I have it all planned out.”