NEW YORK – Michelle Pfeiffer – siren of cinema, three-time Oscar nominee, the woman on the cover of People’s first-ever issue of “The 50 Most Beautiful People in World” – is 51.

She’s been a movie star for 25 years, but no part of the job seems to work for her. Pfeiffer hates parties. She hates premieres. She mourns the loss of her privacy, although taking a five-year hiatus helped. If she had her way, she would not be in a Manhattan hotel talking about her latest movie, “Cheri,” even though it’s her first real lead role in almost a decade.

Twenty years ago she played a doe-eyed girl victimized by social predators in “Dangerous Liaisons.” Now, in another adaptation of French literature with the same director, she plays wealthy courtesan Lea de Lonval, who starts to feel tiny ravages of time when she shacks up with a man half her age.

“Mmm,” she says, contemplating these career bookends. “Literally, the virgin and the whore. And everything in between, from then until now.”

Born in Santa Ana, Calif., Pfeiffer was a beach bum who bagged groceries and was crowned Miss Orange County in the late ’70s. She played Tony Danza’s girlfriend, Suzie Q, in 1980’s “The Hollywood Knights.” Two years later she strutted her way through “Grease 2” in a pink satin jacket. No one came out of that movie looking good, which is why, rumor has it, Brian De Palma didn’t want to consider her for the role of Tony Montana’s cokehead girlfriend in “Scarface.”

But she got that role and created her first enduring cinematic image by entering the film in a glass elevator, wearing a backless teal dress slit to her hips. She had the right look, and now she was playing a bombshell with substance.

“I think it legitimized me, in a way,” Pfeiffer says of “Scarface.” Irresistible beauty was “part of the tragedy of the character. In the same way it’s part of the tragedy of Lea (in “Cheri”). Their survival depends on their beauty.”

Two movies made her the superstar she insists she never intended to be. In 1989’s “The Fabulous Baker Boys,” she stumbled into Jeff and Beau Bridges’ cabaret act as sarcastic call girl Susie Diamond and immortalized herself by rendering “Makin’ Whoopee” atop a grand piano.

Equally iconic was her Catwoman in 1992’s “Batman Returns.” Pfeiffer.

Sexpot and serious actress. Talented and tantalizing.

“I started out really just hoping to make a living,” she says. “I’m sure a lot of people were surprised that I became famous. It wasn’t really my agenda. ... There was no reason for me to succeed.”

She adopted a baby girl and married TV writer/producer David Kelley in 1993, later had a son with him, and made People’s beautiful people list six times that decade while turning out subpar movies (“Dangerous Minds,” “Up Close & Personal,” “The Story of Us”). After 2002’s “White Oleander,” Pfeiffer dropped out to spend time at home.

“She seemed quite uniquely qualified” for this role, says “Cheri” director Stephen Frears. “Her career, her life has been so involved with beauty that it must’ve been a blessing and a burden.”

For her, age is just another contrivance.

“It’s on people’s minds,” she says. “I think people are struggling with the concept of how much do you let go and age gracefully. How much do you try to, you know, fight it and stave it off?”