Jack Lemmon has just had his first permanent.

"Jesus, it's so weird walking around this way," he says. "You spend a lifetime getting recognized -- or trying to -- and all of a sudden you feel like Harpo the Clown or somebody."

Indeed, the effect of billowing white permanent waves, framing one of the most familiar and likable faces of the American cinema, is mildly astonishing. Almost from the start of his career, Lemmon has been the American everyman, "Good Neighbor Sam," as the title of one of his lesser films put it.

But the hair gives you second thoughts. It's a madman's bouffant, one of those bad tricks beauty parlors pull on aging matrons. It points up the wateriness of Lemmon's blue eyes at the expense of their trustworthiness. It wafts mockingly when he turns his head. Against so much stately whiteness, his features look haggard. Gravity, you notice, has tugged at the corners of his mouth, bringing it more in line with the faint stoop of his shoulders.

"It's very odd, isn't it," he agrees. But it's just the troubled look he's after. At 61, Lemmon has taken on one of the monumental challenges of the American theater -- Eugene O'Neill's "Long Day's Journey Into Night." In it, he plays James Tyrone, the once-dashing 19th-century matinee idol, who has squandered his promise over a lifetime of drink and delusion. The character is O'Neill's own actor father; the play, a harrowing exorcism of his family's skeletons.

Previewing tomorrow at the National Theatre, the pre-Broadway production has been undergoing a two-week shakedown on the campus of Duke University. "I love the whole ambiance here, being away," Lemmon says. "Nobody bugs you. I'm not getting phone calls. The air is clear. I can stay more zeroed in that way. I feel like I'm 20 years old, I'm so charged up.

"It's just doing the damned thing with this company that's got me a foot off the ground. I've always known I wanted to play O'Neill at some point. Then when I learned that Jonathan Miller was going to direct it, that excited the hell out of me. I thought, 'Oh Christ yes, because this is not going to be just another revival.' "

That, it is not. Miller, it appears, is intent on "liberating the play from Arlington Cemetery," by which he means peeling off all the incrustations of reverence and awe that have built up over the years. "Long Day's Journey" may be one of the great tragic dramas. Miller sees it also as the story of "shanty Irish," who squabble and fight with such rollicking vehemence that he's got the running time down from the usual four hours to two hours and 40 minutes. And that's without cuts. "People have always confused its title with its length," he notes dryly.

"What it means," explains Lemmon, "is that if you have a family of five, going through the love and hate this one goes through, you do not sit around and wait for the end of sentences. When you parse what O'Neill wrote, you find that you're actually replying to things that are said halfway through the preceding speeches. You really wouldn't wait. So there's tremendous overlapping and interjecting at times. Some of the words will be lost, but hopefully not what's important, which is the emotion. And that man did write with an emotional impact that is incredible."

Lemmon once played John Wilkes Booth on televison and Joxer Daly in an L.A. production of O'Casey's "Juno and the Paycock." But for the most part, his enduring appeal has come from his ability -- in such films as "The Apartment," "The Fortune Cookie," "The Out-of-Towners," "The Prisoner of Second Avenue" -- to suggest that he is one of us, the little man trapped in the contemporary world, our surrogate in the rat race. In your secret fantasies, you might wonder what you'd ever say to Charlton Heston. But somehow you know there'd be plenty to talk about with Lemmon: the boss, the grocery bills, the wife's infidelities or the cat's mange. As wealthy, celebrated and wildly successful as he is, his greatest accomplishment is his continuing ability to remain seemingly our peer.

"Ninety-nine percent of the roles I've played -- more than that, almost 100 percent -- have been modern," he says. "I'm attracted to them because I think I understand the stresses and strains we all go through. The tendency for me is to use my face and hands in a very contemporary way. I talk very rapidly. But I've had to approach this part quite differently. It's 1912 and this guy Tyrone belongs to the grand old school of acting. The task for me is to strip away all my mannerisms in order to get the solidity of the character. It's like putting on a straitjacket. Because Tyrone is solid. He's immovable. Christ, he's a goddam oak."

The ad campaign for "Long Day's Journey" features a large portrait of Lemmon from the waist up, his arms folded, one hand tugging pensively at his chin. There's no sign of his fellow players -- Bethel Leslie, Peter Gallagher, Kevin Spacey and Jodie Lynne McClintock. Lemmon is unhappy about that. "I took one look at it and said, 'Where is everybody?' I swear to you I felt so embarrassed, because nobody is starring in this. Nobody. I mean, good, bad or indifferent, this really is a family. I want them to can that ad."

Superstars don't usually behave that way. But then everybody says Jack Lemmon is different. "He's a nice guy," says the publicist. "Jack? Terrific guy," says the producer. "A sweetheart," says a crony.

"That throws me. I don't know why people say it," Lemmon confesses with a shrug. "I guess someone must have said it once -- 'Jack Lemmon, oh yeah, nice guy' -- and it's been passed down over the years. I've certainly never consciously tried to be that appealing, except in my work. You hope you're accepted for that. But it makes me wonder, 'What? Is everybody else a jerk ?' "

An only child, Lemmon was born John Uhler Lemmon III in Boston's Back Bay. His father was a prosperous executive of the Doughnut Corp. of America, who during World War II hit upon the idea of having the Red Cross deliver coffee and doughnuts to the boys in the trenches -- thereby, Lemmon says, "bringing the doughnut to Europe."

If Lemmon didn't have a silver spoon in his mouth at birth, the family cutlery was more than presentable. It was expected that he would go the route of all good New England lads -- Rivers County Day School, Phillips Andover Academy and Harvard -- before taking over for his father.

While attending day school, however, he was drafted at the last minute to substitute in the school play for a classmate who'd fallen ill. "He had a monologue -- 15 or 16 lines, that's all," Lemmon chuckles. "And the very day of the performance, the teacher said, 'Jackie, you're going to have to do it. Learn as many of the lines as you can between classes. I'll be in the wings and I'll prompt you. You'll wear this hat' -- it was a big, wide-brimmed hat -- 'and this cape.'

"Well, first of all, the damned hat came down over my ears, and the cape that was supposed to stop at my calves dragged behind me. When I strode out on the stage, I looked like Marie Antoinette with a goddam train. They laughed before I even opened my mouth.

"I'd walk over to the wings, and the teacher would whisper a couple of lines to me, then I'd walk back to the center, exaggerating them instinctively. Well, I supposed one of two things could have happened. I could have been mortified. But instead, this little light bulb went off in my head. I felt accepted. Something in me was saying, 'I think I like this.' Well, I stretched that little sucker out for five minutes. From that moment on, I wanted to be an actor. It's all I ever thought of."

At Harvard, he was president of the Hasty Pudding Club, but otherwise succeeded mainly in driving his father to distraction by "doing just enough to get by academically." After kicking around in summer stock, he finally decided to head off to New York and "save the whole damn American theater, which for some reason, no one let me do."

First, however, he hit his father up for $300. Here's how Lemmon relates the scene:

Father: So you don't want to go into the company?

Son: No, you know how it is.

Father: You really need to do this?

Son: Yeah, I need to find out. I've got to try or I'll always wonder.

Father: And you really love the theater?

Son: You betcha.

Father: Well, that's good. Because, let me tell you, the day I don't find romance in a loaf of bread, I'll quit.

In New York, Lemmon cut his teeth on radio and television dramas, then made his Broadway debut in a 1953 revival of "Room Service." The production lasted only 16 performances, but following the time-honored scenario, a talent scout spotted him and he was whisked off to Hollywood, where Columbia Pictures mogul Harry Cohn immediately put him into "It Should Happen to You," opposite Judy Holliday.

"Harry Cohn never got over the fact that he had an actor who'd been to Harvard," Lemmon says. "I think that's why I had a very good relationship with him -- which was rare. He'd always say, 'That's my Harvard boy, over there.' I later found out that the day after I arrived he actually called Harvard to check.

"But if it wasn't for Judy, I'm not sure I would have concentrated on films. I was a snot-nose, I must admit that. I almost didn't go to Hollywood. I would rather have sat around the old Walgreen's drugstore in New York with all the other out-of-work actors, pooh-poohing guys in films. Film was for pretty, curly-haired young men. It wasn't the 'thee-ay-tuh.' "

The experience proved so rewarding, however, that Lemmon stayed on, although he was careful to negotiate a flexible contract with Columbia that allowed him to pursue outside projects. "Technically," he says, "I still owe Columbia four films for about $13,000 each. Technically. It wouldn't hold up today."

With only his fourth film, "Mister Roberts," Lemmon struck the jackpot, winning the first of his two Academy Awards for his performance as Ensign Pulver. (The other was for "Save the Tiger" in 1974.) The career has continued, largely unabated, ever since. "I found out that success breeds unemployment," he muses. "A 'Mister Roberts' comes along right away, and you can't just take any film afterwards. You look for something as good. In any career, you're going to end up doing enough bad films as it is. But if you do a film just for the sake of working, you're in trouble. Your popularity goes down -- and that's all it's based on out there: how popular you are, not how good an actor you are. And all of a sudden you're not offered the better scripts. So you have to be choosy. And you wait. It's like telling an athlete, 'Don't exercise for two years. Just show up for the big race.'

"Some of the films have been real uphill fights -- 'Days of Wine and Roses' or 'Mass Appeal.' Hell, 'Mass Appeal' was fighting all the way up a cliff. But I wouldn't take any of them back. I never did a film I didn't want to do."

In a way, Lemmon has been creeping up on the role of James Tyrone all his career. Initially typed as a light, breezy comic actor, he can't entirely shake the image. Still, as the ravaged dress manufacturer in "Save the Tiger," the garrulous Irish priest in "Mass Appeal," the sodden alcoholic in "Days of Wine and Roses" or the distraught businessman who discovers in a Chile under siege that his son is "Missing," he has revealed some of the brute anguish behind the cockeyed grin audiences have always found so appealing.

Recently, Lemmon was honored for the body of his work at the Pan American Film Festival in Cuba. He was allowed to pick the films he wanted screened for the retrospective -- save one. "I thought, 'Well, I know the one they want to screen -- either "Missing" or "China Syndrome," because they're critical of America in some respect.' Wrong! They wanted 'Some Like It Hot.' It turns out it's the most popular foreign comedy they've ever had in Cuba and it's a particular favorite of Castro's."

Castro, Lemmon says, told him so. "I spent about five or six hours with him. He's up all night and he loves to drop in on homes of various friends, especially if there's any kind of party going on. Christ, is he a charmer. He has a terrific sense of humor and a delivery Milton Berle would have loved to have had. This guy can do 15 minutes on 'Hello!' I told him, 'Look, if ever you get fed up with all this crap, I'll be your agent. Man, could I get you some bookings.' "

Lemmon admits he took some "pinko commie" flak for going to Cuba. He also found himself momentarily at the center of the controversy swirling around "Missing" after that film was denounced by the State Department for suggesting that the CIA had a role in engineering the overthrow of Chile's President Allende. (Lemmon had dinner shortly afterward with the Reagans and says their only reaction to the film was Nancy's comment: "We wish the ending had been different.") At the Raleigh-Durham airport the other day, a pamphleteer, campaigning for more nuclear power, called out, as Lemmon passed, "Hang Jane Fonda and hang you, too!" That's lingering fallout from his performance as supervisor of an unsafe nuclear plant in "The China Syndrome."

Mostly, however, Lemmon has stayed out of the public eye, politics and the gossip columns, except for those rare occasions he chooses to fight the uphill fight for a film. He has been married for 25 years to occasional actress Felicia Farr, lives quietly in L.A. and avoids the splashy parties. To unwind, he composes songs on the piano. They are not as good as those of Gershwin, his idol.

The Lemmons have three children: a daughter of their own, and a son and another daughter by prior marriages. "I've spent my whole life avoiding nepotism," he says. "And I just did a picture with Blake Edwards, called 'Crisis,' which I think they've renamed 'That's Life.' Anyway, Julie Andrews plays my wife. Julie and Blake's two daughters play our two daughters. And Chris, my son, plays our son. Then, suddenly, damned if Felicia doesn't get in the film, playing a gypsy fortuneteller, who seduces me in five minutes. But I figured what the hell, if you're going to have to commit adultery, you might as well do it with your wife."

Lemmon chuckles, puts his feet up on the coffee table, and lights up a cigarette. He gave up liquor two years ago, "because it began to bother my gut and my whole body. I'm too compulsive." But he's still smoking two packs a day and temporarily rationalizing the habit as a way of keeping his voice deep. "The lower I get it for this part, the better," he says.

Here, in a hotel on the fringes of the Duke campus, away from the retinue that usually surrounds a movie star, Lemmon seems exactly what he says he is: a working actor, visibly excited to be going back to Broadway, where he last triumphed eight years ago in Bernard Slade's comedy-drama, "Tribute."

"I guess there is a certain kind of blind stupidity to the profession," he muses. "I mean, if someone said to you, 'Look, we've run everything through the computers and you have only one chance in a million of making some kind of living as an actor, let alone having the kind of success you dream of,' you have to be able to say, 'Yeah, I'll do it.' And you really have to believe it. Because on top of that, you're going to have disappointment after disappointment.

"I love acting, I really do. I'm always looking for terrific parts. But you know the ones that interest me? The parts I don't know how to play when I read them. I'm getting to be a middle-aged dinosaur. But the only ambition I have is the only one I ever had: to get better, to be as good an actor as I can be."