BY DINITIA SMITH

I'm scared!" said Uma Thurman. Ms. Thurman, all 5 feet 11 1/2 palegold inches of her, was about to perform live for almost the first time in her life, in an update of Moliere's "Misanthrope" at the Classic Stage Company, a 180-seat theater in the East Village.

On screen, Ms. Thurman is known for lowering her forehead, looking up at men from under her brow and talking to them in a husky come-hither voice. In films, there are retakes, camera tricks, and you need only learn a few lines of the script at a time. When acting for film, Ms. Thurman said,"you can fantasize about the good moments in each take and how it will be put all together, and leave it in trustworthy hands" of the editors. But in the theater, she said, "you're the final word."

The production with Ms.Thurman, now in previews, opens on Sunday.

Why would she want to do it, risk making a fool of herself in a role that must be recited almost entirely in rhymed couplets? Is Ms. Thurman trying to "stretch"? That is a word bandied about a lot as film stars take to the stage. She is in line with a string of movie stars who have been trying theater lately, including Nicole Kidman in David Hare's "Blue Room," based on the Arthur Schnitzler play "La Ronde," and John Turturro at the Classic Stage last December in "Waiting for Godot." Last year at the Joseph Papp Public Theater Alec Baldwin and Angela Bassett did "Macbeth." Kevin Spacey is about to perform in "The Iceman Cometh." Ms. Thurman's husband, Ethan Hawke, still does a little theater.

The original "Misanthrope" is the story of Alceste, a man of letters and amoral snob who inveighs against the sycophancy and hypocrisy of the court of Louis XIV. He is in love with a much younger woman, Celimene, whom he suspects of having affairs with everyone around her. In the new version of the play by Martin Crimp, Roger Rees, who won a Tony award for best actor for his role in "The Life and Adventures of Nicholas Nickleby," has the role of Alceste, who is now a playwright. In Crimp's play, Celimene becomes Jennifer, an American movie star in London. Michael Emerson plays Alceste's friend John. And Nick Wyman is Covington, a talentless critic who insists on reading his play to Alceste.

Celimene, the leading lady in the original "Misanthrope," is one of the theater's more difficult roles. Is she simply a coquette? Or does she possibly love Alceste, who is driving her away with his hectoring?

It is "a very hard part," said Ms. Thurman. "I'm still really searching, working." She must also hold her own against Rees, a veteran of the Royal Shakespeare Company, who is a strong and self-confident stage presence. Like a chamber music piece, the play requires precise timing and delicate interplay between the principals.

The new "Misanthrope" is a challenge for not only Ms. Thurman, but for just about everybody connected with the production. It is being directed by Barry Edelstein, who is in his first season as artistic director of the Classic Stage Company. And Crimp, instead of relying on the 1954 Richard Wilbur translation as many contemporary productions do, has retranslated the play.

Crimp,who also translated Ionesco's "Chairs" for Broadway, has now tampered with a play revered in the canon and filled it with hip references. Like Moliere, Poking Fun.

The new version closely follows the form of the original and maintains the tradition of mocking real people, as Moliere did three centuries ago. Crimp refers to David Hare unflatteringly and parodies his play "Skylight" in the critic Covington's dreadful play. Crimp's Jennifer also makes fun of a certain magazine editor: "Now there's an editor with no imagination/who's managed to carve out a reputation/ for being at the cutting edge/by draining meaning out of life and language." Edelstein said the character "is modeled on Tina Brown," a former editor of The New Yorker.

Then there is a movie director who, Jennifer says, "imagines he's the height of moral bravery/for writing scripts that deal with genocide and slavery./Believes he's wise, but what he's done is crossed/the feel-good factor with the Holocaust." The lines are an allusion to Steven Spielberg, said Edelstein. "She's sending up famous people in order to show off how witty and clever she is," he explained.

Further insults include references to an Andrew Lloyd Webber musicalas "a natural disaster" and an Alan Ayckbourn work as "one more mediocre British play/hailed as an artistic triumph in the U.S.A."

But most interesting for audiences in London, where the play opened at the Young Vic, has been Covington, who is a mixture of two powerful British theater critics, Michael Coveney and Michael Billington. The critics took revenge in their mixed reviews of the London production. "A middle-aged, menopausal white male specimen named Michael Covington," Coveney wrote in The Observer. "Not an amalgam, surely, of myself and Michael Billington? Pretentious, badly dressed -- nous?"

Still, Coveney called the production lively. And Billington, reviewing it for The Guardian, said it was "agile, topical and cheeky." But, he wrote, the "vain and posturing theater critic called Covington -- can't be one of us, surely?"

Ms. Thurman said before a rehearsal, "I don't agree with that name-using."

But Crimp, in a telephone interview from London, defended the allusions. Speaking of his references to the critics, he said, "I would say it's a compliment to both of them." The play, he said, is meant to be "an attack on the theatrical establishment, highbrow theater."

Edelstein said the references were in keeping with the Classic Stage Company's mandate "to produce the classics from a contemporary point of view, rather than just reviving" them. With an updated play "an audience in New York has the same sensation the audience had in 1666 in the court of Louis XIV," he said. "The audience is sitting there: 'Omigod! I can't believe he just said that.' "

In deciding who should play Jennifer, Edelstein said he thought "it would be a charge to have a movie star playing off this great English classical actor," Rees. He chose Ms. Thurman, he said, because "I knew her to be an actress of style."

Ms. Thurman, whose films include "Pulp Fiction," "Gattaca" and "Henry and June," said that when Edelstein first approached her, she almost turned him down. "I thought he just wanted me for hype," she said. But, "he was so passionate about the piece."

"I'm going through an interesting time in my life," said Ms. Thurman, who is 28 and had a baby daughter nearly seven months ago. "I'm willing to begin again." Ms. Thurman, who comes from an intellectual family, said she needed the challenge. Her father is the Columbia University professor Robert Thurman, an expert on Buddhism. "I felt compelled to do something in which I would be forced with pain or pleasure to grow."

Then there is Maya, Ms. Thurman's daughter. Movies seem out of the question right now. "Does a child want to hang out in a trailer?" Ms. Thurman asked. Her husband, who has published one novel and is working on another, has taken over caring for the baby. And during her long break, Ms. Thurman can bike home to their loft to feed Maya. "It's a miracle to memorize an entire text and be a mother," Ms. Thurman said, because of "the presence of progesterone in your brain."

In late January Ms. Thurman and the company rehearsed in a borrowed space at the Atlantic Theater Company on West 16th Street in Manhattan. In some ways, rehearsing a play can be like making a movie in fragmentary takes.

"You see, I'm sure the moral values we apply/undergo subtle changes as the years roll by," Ms. Thurman, as Jennifer, said in an arch voice.

"Wonderful, Uma," Edelstein later said of her reading. "The more it drips the funnier it is."

During a rehearsal of a costume-party scene, Ms. Thurman recited Jennifer's lines: "Play us some music. And nothing too arty./I'm sick of this. I want to party." Ms. Thurman began to dance, gliding swanlike about the room to the music of the Pet Shop Boys, singing "Always on My Mind." "If that's the life you want to lead," Rees, as Alceste, said to her, "so be it. Just don't come to me when you need/ help, because I shan't be there./You may not believe in despair/but I do."

At one point, Ms. Thurman interrupted a dance rehearsal to say she didn't think she should move around too much in the baroque dress. She had tried on the costume and the bodice was very tight. "It'll look silly," she said. "You'll have to get someone else."

Edelstein rushed to placate his star. "No, never anyone else," he told her.

Now, one by one, Ms. Thurman lured the members of the company into her dance, stopping in front of each one, looking up under her lowered brow and extending a long arm as Edelstein watched.

"Everybody's adoring her," he said of Ms. Thurman's Jennifer. "Bathing in the light of her triumph. She wins."