Rex is vexed.

"I wish you'd stop talking about that book," he bellows. "I don't like it. I wish you wouldn't quote from that. I thought we were going to talk about 'Aren't We All?' "

The book is his 1974 autobiography, "Rex" ("pure rubbish"), and "Aren't We All?" is the drawing-room comedy he and Claudette Colbert bring to the Kennedy Center tonight for a four-week run.

Arrogant. Tyrannical. Impatient as ever, Rex Harrison is barking at a reporter who has been reduced to the stature of a squashed cabbage leaf. A mutton-headed dolt, an impudent hussy, so deliciously low.

Let a scribbler in your life and you invite eternal strife. Like Professor Higgins -- the irascible misogynist in "My Fair Lady" -- Rex Harrison is a man who has made a reputation living exactly how he likes and doing precisely what he wants and if you think he's mellowed, he has not. A most sophisticated 77, Sexy Rexy ("Walter Winchell started that, much to my annoyance") is still sparring, still snarling.

"Snarl," he says, "or snore."

Harrison is sitting in his hotel suite, wearing a gray suit, lime-and-pink tie, red socks and thick spectacles. He is tall and aristocratic-looking, with fine wispy hair and dapper bearing. His voice alternately booms and belittles in clipped, baronial tones, and one eyebrow seems permanently cocked in a curious blend of bemusement and disdain. Speaking of those "beetling" eyebrows, New York Times drama critic Walter Kerr recently observed, "I think they have at last merged and can no longer be referred to in the plural."

His wife Mercia is resting in the next room. She is his sixth wife. His first was Marjorie Thomas. He left her for actress Lilli Palmer whom he left for actress Kay Kendall who died of leukemia two years later. (Harrison kept the illness secret from her.) Then he married actress Rachel Roberts and he left her for Elizabeth Harris (former wife of Richard Harris), to whom he dedicated his you-know-what.

"I wish you hadn't read that book. I wrote it a long time ago. It's not the way I think now, and I wish I hadn't written it. I don't think people should write until they finish their careers. I wouldn't quote anything from that, if I could advise you," he says, peering over the tops of his glasses like an Oxford don in a tedious tutorial. "I don't want to discuss it."

Harrison once observed that stars appeared to be the same people on screen and off. It wasn't acting. Cary Grant was Cary Grant. Gary Cooper was Gary Cooper.

Rex Harrison was Rex Harrison?

"I would think so," he allows. But "I don't even really agree with that now. I don't know what I was at that point, because unless you're a character actor essentially you do use your own elements in acting. I think I was talking rubbish."

He was quite rambunctious in his younger days.

"Oh yes." He momentarily brightens.

Had quite a life.

"I have."

Yachts anchored in Portofino, Italy. Garbo over for cocktails. Noel Coward. Cole Porter. Rolls-Royces. And all those glorious, sexy women.

"I have had quite a life. I must say I've worn it pretty well."

He chuckles for the first time, a delightful high-pitched laugh.

In his book, he mentioned . . .

"I wish you'd forget that BLOODY BOOK!"

Claudette Colbert and Harrison appeared together on Broadway in 1978 in a revival of "The Kingfisher." They are social friends as well as costars. Yes, she says, he can be difficult.

"He's very impatient. With everybody," she says wearily. "He likes things his own way, and he's rather difficult during rehearsals."

Still, she says, "he's a wonderful actor and a great comedian."

Back in his hotel suite, Harrison is asked, rather meekly, if it gets any easier with age -- or if, like Glenda Jackson, he is seized with the queasy feeling that each time he goes on stage it is for the first time.

"No," he grouses. "She would say that. We all have to combat nerves."

How does he do it?

"All sorts of ways. You're not going to get on the stage unless you have a nervous temperament, so you've got to suffer it and play as much as you can."

Maybe you only do it because it feels so good when you stop?

"Up to a point," he says with a tight smile. "Except you're practicing your art. You relax afterwards and you feel that you've done something to entertain a body of people, take them out of themselves. I think what we do is of great service to humanity, if you want to be pompous about it.

"I think acting is a calling," he pronounces. "I went on the stage when I was 16. I think good, bad or indifferent, you have a calling. You have a lot of bad actors who continue to do it. They don't give up. Very few actors, even if they don't get work, totally give it up and go and do something else."

Might the process also be a way of getting out of himself?

"We call it 'Dr. Theater,' " he agrees. "We can come in feeling absolutely lousy and feel better afterwards. Of course, one has an obligation to the audience and so one has to be very careful not to get cold. I caught a virus in San Francisco. Went straight to my throat. I didn't dare be off. I kept going. That's what you have to do. It's not all beer and skittles," he says merrily. "Damn hard work it is."

As for the idea of celebrity, Harrison says he can do without it, but "You get certain perks." His, for example, is a limo. He brings his own wine to the Kennedy Center dressing room. "And if you're clever you can make a lot of money." But fame "is very irritating, as a matter of fact, because you get stopped in the street. People come up to you just as you have a large piece of food on your fork about to enter your mouth. They want to say hello or something.

"I'm totally antisocial. I don't like going out. I lead a very private life and have my set of friends. I'm not part of celebrity time in any way."

As for his craft, then, it does get easier with age and experience . . .

"I didn't say it got easier," he growls impatiently. "I don't think it gets any easier. It's always more or less the same. We all have to suffer."

He was born Reginald Carey in 1908 near Liverpool. His parents were upper-middle-class, and Harrison says his own driving ambition is a direct result of his father's lack of it.

Acting indeed was a calling. He started as a teen-ager, appearing on the stage and then in several low-budget films. Signed by Alexander Korda, Harrison made a small splash playing breezy parts ("Storm in a Teacup"). He was described by film historian David Shipman as "an odd looking man . . . wiry, thin faced, with rather bulbous eyes."

He continued to work in regional theater as well as the West End and was a hit in Noel Coward's "Design for Living," followed by the 1941 film "Major Barbara." Appearing in the 1945 film version of Coward's "Blithe Spirit," Harrison found his niche as one of the best British light comedians of his generation. After the war (he served as an officer with the Royal Air Force) he went to Hollywood.

He made more than 41 films in all, and appeared in countless theater productions both here and abroad. He played Henry VIII (in "Anne of the Thousand Days," for which he won a Tony award), King Mongkut in "Anna and the King of Siam," Caesar to Elizabeth Taylor's "Cleopatra."

Until his 1956 stage portrayal of Professor Henry Higgins (another Tony), Harrison seemed an actor in search of a part. "My Fair Lady" made him a superstar, winning him an Oscar for Best Actor of 1964. But critics noted that the actor had a knack for choosing bad scripts and never attained the stature of the more serious voices of his generation. Ralph Richardson. Gielgud. Olivier.

"I didn't want to become Olivier," he says. "I think I've chosen very well. I never had the slightest desire to play Shakespeare. I've always enjoyed playing comedy. I've never," he says, crossing his legs, "done anything I haven't wanted to do."

In fact, he wasn't convinced he wanted to do Higgins.

"I took a long time to decide whether I should do it or not. I must say, you probably don't know, but Shaw didn't like the idea of his plays being put on. You know why? You know why?"

He pauses impatiently.

"No? Because one of his plays, 'Arms and the Man,' was turned into a musical without his permission, called 'The Chocolate Soldier.' "

The important thing is, he did play Henry Higgins. It was the part of a career. The part of a century.

"Everybody thinks I did it for my entire life. In fact, I only did it two years abroad and one year in London and took a year to make the film. That's all. I mean, it was a high spot in my career but it didn't go on because I didn't want it. I wanted to do other things."

He agreed to a revival in 1981. "I could have played it the rest of my life," he says with disdain. He was determined not to get stuck, like Yul Brynner, who made a career out of "The King and I."

"I don't know how he did it. It's become so boring. There comes a time when you either want to do something else or you want to stop doing the whole lot!"

Having one enormous success, one perfect role, he says, was more satisfying than having a string of mediocre ones.

"Yes. Obviously. It was wonderful."

But Henry Higgins wasn't enough.

"It hasn't been enough because I've done hundreds of other parts." He gets up, crosses the room and fishes out a second pair of glasses from a coat pocket. He turns, aiming the glasses like a pointer. "I'd like to have five or six masterpieces! But I'm not saying it was my masterpiece. It was absolutely a group success. Moss Hart had a lot to do with it because he directed it in London and New York.

"They came over to see me, you see, Lerner and Loewe, when they had only written three quarters of the music for 'Pygmalion.' The only thing that worried me, obviously, was the music."

He was not a singer.

"No I wasn't. Never have been since, actually."

The songwriters tailored the music to Harrison's limited range. Some would say 1 1/2 notes. Shaw, of course, never saw "My Fair Lady."

"Actually, I thought about him quite a lot when I was doing it, I must say," Harrison chuckles. "At what his reaction would have been at the end. He wouldn't have liked it. For one thing, in the original production, Liza marries Freddy Hill."

What!? Marrah Freddah? Eliza Doolittle runs off with the wimp?

"Yes," Harrison mumbles, "the wimp, yes."

Rex was never a wimp.

"No," he snarls.

Both he and Cary Grant managed to translate their smooth English manner into something more masculine. Not exactly that "creamy English charm" Evelyn Waugh once described.

"No," he says. "I loathe that."

In fact, "Sexy Rexy" could be a pain in the necksy. He once slapped Frank Sinatra, was blamed for the suicide of actress Carole Landis (with whom he was having an extramarital affair) and was known as cocky and defensive, especially with reporters. He was reportedly blacklisted by gossip mavens Louella Parsons and Hedda Hopper, who pronounced him "box office poison."

"They were extremely impolite to me," he recalls. "If they'd been polite I would have liked them. They had a devilish power. It was ridiculous. People were actually frightened of them! I didn't give a damn. I hated them. I hated them for the way they treated other people."

These are a few of his unfavorite things: current films, Hollywood, talking about his ex-wives.

"I wish you wouldn't bring up that book again."

His role in "Aren't We All?," he says, is a sophisticated, stylish, witty one. Both he and Colbert are pleasantly surprised that the play (a revival of the 1926 original) was a recent smash on Broadway and seems to appeal to all ages.

"A friend of mine, Geoffrey Beene, saw it in New York," says Colbert, "and said, 'It's so nice to have conversation again.' "

Drawing rooms. Smoking jackets. Gin gimlets. The original beautiful people.

"Absolutely gone," Harrison laments. "Isn't it funny? Who's taken their place? Pop stars." He spits out the last two words like olive pits. "It's pretty odd. I hadn't really thought of that, but it is extraordinary. I don't think it suddenly started with Cole Porter and Coward and the Lunts."

The doorbell rings. A waiter has arrived with lunch on a tray. Harrison looks relieved. "This is rather like shoving you out, I'm afraid," he says with a wicked smile.

He enjoys his status as Living Legend. He knows he's damn lucky to still be around. Even if it does mean doing revivals.

"It's very nice indeed," he quips, "but when everybody else drops off the tree, you think, 'What the hell am I doing here?' "