What you remember is this: He is a slight and fragile youth, the fine light hair always tousled: wimpy, but for the assertive aural transgressions of a British working class accent, which somehow conflicts with his intense pallor. And the pallor is the only intense characteristic he has. For the rest, he's the passive dreamer of "Billy Liar," the revolutionary Strelnikov of "Dr. Zhivago," and - of course - the loneliness of the long-distance runner.

What you see is this: Tom Courtenay glances hesitantly about the imposing gold-and-white decor of the Ritz-Carlton restaurant. He is now 39, and the years have made him not portly, but decidedly solid; the flesh pink now, the frame - a square frame - covered by an unremarkable brown suit. Accompanying him is his wife, Cheryl Kennedy, who looks his Carnaby Street as it once was: all blond hair and large eyes framed by Twiggy-length lashes.

What you hear is this: "All I've done is watch football games, that's all. Cheryl doesn't believe me but it's true." Kennedy, also an actress, is visiting this country for the first time, and practically has just arrived.

"Albert Finney," continues Courtenay, "when he was here in 'Luther,' took me to a football game." He shuts his eyes. "It was Y.A. Title playing for the Giants. The Giants against the Redskins, and the Giants by the way won easily. So I've been explaining football to Harold Pinter. Oh yes, Harold loves sports, and he likes cricket very much. I used to play the odd bit of cricket with him."

Harold Pinter, as it happens, is now directing Courtenay in Simon Gray's "Otherwise Engaged," which opens at the National Theater today. At this moment, he, too, is eating lunch at the Ritz-Carlton restaurant.When he rises it's to stop by Courtenay's table to greet him. But after the introductions are made (and the word "report" mentioned) he wisks off with, "I'm off to Canada."

Harold Pinter, it should be said, has not been terribly anxious to greet the press, and the press's gleeful reports of his romance with historian Lady Antonia Fraser might have heightened his reluctance.

"It's always 'Lady Antonia,'" Courtenay says, returning to his wife. "Americans like aristocracy." The waiter stops by his table to inquire about the wine. "I tell you what I like," Courtenay replies. "I like Gallo wine. It's quite nice," he concludes, oblivious to the waiter's look of mild surprise.

"I suppose it's not grand enough for this place," he murmurs later, and the unassuming nature is one of the few remnants from the old days. It's the kind of thing that prompts him still to say, "I like doing low-budget films. Well, I don't like to take liberties." Then he attacks his cold salmon with a relish so enormous that it almost erases all the memories of the internally combustive weakling. The meal is topped off with Boston cream pie.

"I put on a bit here," he says, non-chalantly patting his stomach. "See, I usually go running to get in shape. I shall have to start running again. I'm a bit heavier than usual.When I played Ivan Denisovitch, I slimmed down for that. Well, I thought it only fair."

"One Day in the Life of Ivan Denisovitch," a movie based on the novel of life in Siberian camps by Solzhenitsyn, was in fact, Courtenay's last film."It's been four years," he says, "and they just don't make the low-budget films that used to be shown in England. That's all past."

And the Tom Courtenay that used to be is also past.

"You're a man now," his wife informs him. "A mature man now."

He does not look pleased. "I wouldn't go that far. I hope it will come. But it wouldn't do to be too mature for any role.

"When I first started out," he continues matter-of-factly, "I was very vulnerable and skinny and very touching, I dare say. I've been told these things . . . All those people who were writing, were writing things to fit me."

The Angry-Young-Men movies?

The corners of this thin lips descend just a fraction. "Nouvelle vague, we called it. That's from the French - the new wave. As it turned out it was easy (to get started). The trouble is I wasn't really very good. I was rather limited. And that was the price I had to pay for really being well-known rather quickly."

The way Courtenay got well-known rather quickly was through "The Loneliness of the Long-Distance Runner," in which he played a mercilessly sportive inmate of a reform school who neither beats nor conforms to the system - he simply withdraws from the running. At the time they were shooting the film he was simultaneously appearing in the play. "Billy Liar" at night. A year later he would star in the film version of that, as well.

One of his particular triumphs (and it was no doubt an easy one) was that he was what he appeared to be on the screen: a young man from a working-class background, and the antithesis of all the drawing-room drama pretty boys who had preceded the New Wave. He was born in Hull, Yorkshire, the son of a man who painted fishing boats.

"All of us were set on the idea of my bettering myself," he says. "Through being educated. Yes, it appealed to them very strongly."

In 1958, he went on scholarship to the Royal Academy of Dramatic Art, and from then on his career proceeded with absurd smoothness. Tony Richardson saw him in an Old Vic production of "The Seagull" and cast him without a screen test for "Loneliness." He was then 24.

"It was a big rush. I was probably so young I didn't realize what was happening . . . It was probably quite a good thing that the firms I had earlier weren't that successful (commercially). Well, I think that could have been the ruination of me. For all the rubbish I had in me, I also had a bit of common sense.

"I was very concerned that I was quite well-known and not very experienced. After 'Zhivago' I wanted to get more experience. I got into a low ebb. I had earned a bit of money. But I wasn't getting anywhere and I thought my future lay in doing good work on stage."

And so he did plays like "Time and Time Again," She Stoops to Conquer" and now - "Otherwise Engaged," which began in England with Alan Bates.

"It's a very clever idea, really. A man has put aside a day to play his new Wagner album - Parsifal, but really it could be anything. And he never gets to play it. Finally, when it ends and the curtain drops, you can hear the music.

"We were a bit concerned when we saw in the (Boston) paper about how "Otherwise Engaged" is becoming a cult here. Then the article said that it will be too clever for the people in Washington."

Impassively he gazes at the interviewer, demanding neither a denial nor an agreement. It's just a concern.

One of many concerns, in fact.

"You know the National Theater? It's awfully big, isn't it?"

"Yes," interjects his wife, "but it will be good because your (voice) has to come back out and it's good for the others as well.

"Yes, but the vareity of pitch, if you have to fill a big house . . ." Courtenay almost frowns when he thinks of it. "Of course you can go softer in a small house. Harold (Pinter) - I just spoke to him, and he said, 'Well I think you don't have to worry.'"

For a moment - a very brief moment - he looks like what he once looked like: a man who could be easily wounded. He is asked if he misses that.

"Oh goodness me, no. It's nice to change. People change throughout their lives . . . Nov, I'm particularly after a new thing, sort of finding the interior of things. Robert Shaw phoned me, and he told me what an old actor once said to him.

"He said. 'You know, Robert, in my day when we had a bad line, we found a good way of saying it.'"

The impassive gaze returns. "I used to be vulnerable. But I've got a bit of skin now. I didn't have any then. I don't give it a lot of thought."