Liliane Montevecchi Lives Her Role Offstage Too : Theater: Actress brings show biz persona along as ‘Grand Hotel’ goes on the road.

There are ordinary show folk. There is Liliane Montevecchi. There are differences.

Your normal actor, for instance, rehearses in casual clothing. The touring company of the musical “Grand Hotel,” finishing one of its final run-throughs in an empty theater on 41st Street, is in sweat pants, leotards and jeans.

Montevecchi, however, adores capes and cloaks, always wears full makeup and--her trademark--a hat. She always dresses in a single color. Her rehearsal ensemble this afternoon is entirely ivory, from felt cloche to mega-pearl earrings to high-heel pumps.

“My eye loves ‘armony, yes,” she declares with heavily French-accented grandeur. “Everything has to be co-ordeenated, otherwise I don’t go out.”

The other cast members on the tour are on a first-name basis. But Montevecchi, whose personal wardrobe (including 50 chapeaus) will be toted coast to coast in a vast hinged crate painted red (“because red ees my color”), is known as Madame.

It’s a reference not only to the once-celebrated ballerina she plays in “Grand Hotel,” but to her regal bearing offstage as well, and Montevecchi accepts the nickname as her due. “It’s nice, like ‘aving respect,” she says. “It’s not pretentious; it just gives a leetle glamour.”

A leetle? Montevecchi--born, need it be pointed out, in Paris--wears her lashes longer than those that grow naturally on the human eyelid and her fingernails even longer than that. She thinks realism is overrated. She’s show biz with a capital show.

She’s playing the part that Garbo created in the 1932 movie, but Montevecchi’s basing her interpretation on somebody else. “Moi!” she announces, laughing throatily, chin tilted impossibly high. “Because it’s exactly what I am. I’m exactly the right age, and I’m always falling in love with someone very young. Or they fall in love with me. We have a certain attraction.”

And why might that be? “Maybe because my energy is very high up, because I’m amusing,” Montevecchi considers. “I don’t know why. I don’t want to know why. I just want it to continue.”

It’s been a little more than a year since “Grand Hotel” opened on Broadway with Montevecchi as Elizaveta Grushinskaya, the aging dancer on her umpteenth farewell tour. (Originally conceived as a Russian ballerina, Grushinskaya became a Frenchwoman a week before the opening because Montevecchi’s Francofied version of a Russian accent wound up sounding, she confesses, “like Japanese.”)

The critics were fervid about director and choreographer Tommy Tune but less effusive about other aspects of the musical; they tended to leave the theater whistling the staging. Nevertheless, Montevecchi got a Tony nomination and a long run (the show’s still playing at the Martin Beck Theatre) and, eventually, a case of restlessness.

She’s the only star of the original production embarking on this year-long expedition: Atlanta, Pittsburgh, New Haven, Syracuse.

She began as a ballet prodigy in France long ago. (How long? “What is age? It’s a number,” she says, an airy dismissal. “Some people like to have a little mystery.”) She was a prima ballerina with Roland Petit’s dance company, then won a seven-year contract with MGM. (“It is easy to figure out, if I tell you I was at MGM in the ‘50s,” Montevecchi allows, on the age issue. “But I’m not going to tell anyhow.”)

She had small parts in a few movies; she had some fun. “I had a collection of sports cars,” she remembers. “The palm trees and no smog.” But she was not unhappy, she says, when her contract lapsed. “I’m never upset about anything.” Distress causes wrinkles, perhaps.

For 10 years she starred in the Folies-Bergere in Paris, Las Vegas and New York until she figured, “Enough of carrying feathers.” In 1982 she won a Tony for the musical “Nine,” also directed by Tune. She has a cabaret act as well, weaving Aznavour and Brel and Piaf into a tuneful kind of autobiography.

In her artful artifice, Montevecchi seems to belong to some earlier and grander theatrical tradition; she’s, well . . . “Flamboyant, always,” she supplies, helpfully. “You see, my mother was like that, very, very chic.” Her mother, a Parisian model and designer of hats, “always wore a Chanel suit and pumps. . . . Even in the house, she would not wear slippers,” lest her feet grow too wide for fashionable footgear.

Now, Montevecchi feels semi-clad without a hat, preferably one with a substantial brim. “I like them like little umbrellas so I can hide underneath.”