Outside the Kennedy Center last night, the limousines lined the driveway like a long glamourous freight train.

Inside were a glittery crowd of 1,200 and the five recipients of the 1980 Kennedy Center Honors for lifetime achievement in the performing arts -- actor James Cagney, composer Leonard Bernstein, diva Leontyne Price, choreographer Agnes de Mille and actress Lynn Fontanne. After a three-hour gala tribute in which a variety of well-known celebrities performed and spoke, the honorees sauntered into the grand foyer to choruses of applause. aAs Count Basie warmed up the ivories on his gleaming Baldwin, admirers of the five settled in to dine and then flowed onto the dance floor electrified by the Basie beat.

Tennessee Williams and Maureen Stapleton didn't even make it to the dance floor. They spun each other around between the tables, snapping their fingers to music syncopated by the rhythm of popping flash bulbs.

"I was nervous," said Agnes de Mille. "I was putting on a new show tonight" ("Texas Forth," a dance performed at the ceremony). As she sat at her table ready to dig into her food, she groused politely about having to answer yet more questions in a day full of them.

Honoree James Cagney was flanked at his table by ballet dancer Mikhail Baryshnikov -- tie off and white-collared shirt open -- and a woman who fended off photographers and reporters. Also at the table was veteran actor Pat O'Brien, who had given a speech about Cagney during the gala.

"It was no speech," said O'Brien, smiling. "It came from my heart. I've been friends with Cagney for 55 years. My daughter said to me, 'You and Uncle Jimmy cry at the opening of supermarkets.'"

Around the room people had begun to relax as if transported back to their favorite high school dance. Actress Jane Seymour had literally let down her waist length hair.

At one end of the long, crowded, red-carpeted hall sat Beverly Sills, still a bit giddy from the excitement of it all. "I was the last one at the White House, you see. I was rehearsing all afternoon."

The White House earlier had been just bursting with movie stars and political celebrities.

Introductions at the White House:

Lauren Bacall asked Eunice Shriver: "Do you know Mikhail Baryshnikov?" The dancer himself was introduced to the wife of Sargent Shriver. "He's dancing here in town," said Bacall. "You should see him if you can -- that is if you can tear yourself away from the tennis court."

In the Red Room: "Hi. I'm Jacques D'Amboise. I'm a dancer," he said, introducing himself to Donald Sutherland, the actor. "I really can't tell you how much I admire you."

"Who do you dance with?" asked Sutherland.

"I dance with the NYC Ballet. I'm on the artists' committee for the Kennedy Center Honors."

"Me too," said Sutherland.

"They didn't take my advice. None of the people I recommended won," said D'Amboise, laughing.

It was like that last night at the White House, a labyrinth of elegant rooms where tuxedoed and chiffon-swathed movie stars encountered other movie stars, not to mention playwrights, congressmen, senators and White House officials. The occasion was a reception before last night's Kennedy Center gala.

President Carter gave remarks a little after 6:30. "I think almost every American must have a Jimmy Cagney impression," said Carter. "When Cagney came through the receiving line, we agreed we would not exchange Jimmy impressions."

"Cagney," said Gerald Rafshoon, President Carter's media adviser. "God. He's great." Rafshoon had walked through the Red Room, where Cagney was receiving admirers, but Rafshoon simply admired from afar.

One who didn't admire from afar was presidential assistant Anne Wexler. She thrust her head through a crowd around playwright Tennessee Williams, a Kennedy Center Honor recipient from last year. "Remember me?" Wexler asked, shaking Williams' hand. "We worked together on the Medal of Freedom."

"I'm working on a play called "The Everlasting Ticket," said Williams. "But don't worry. It's in no danger of making it to Broadway."

"It's a trip." said one young, very handsome actor who did not want to be named looking around the Red Room of the White House. "I've never been here before."

More chance encounters:

Eli Wallach, the actor, spotted Donald Sutherland. "I haven't seen your movie yet," said Wallach, shaking Sutherland's hand. "I hear it's excellent."

"That's Richard Gere," said Tennessee Williams' assistant, pointing out the actor made famous by the movie "American Gigolo." "Mr. Gere!" bellowed Williams. Gere glanced up, knelt before Williams, then reached up for the playwright's hand. "I want to stop a certain story you've been spreading . . ." said Williams. But then the two whispered conspiratorally, and the story was lost to bystanding ears.

Jane Seymour, who has been performing in "Amadeus," which finished a run in Washington last night, saw Gere. "What are you doing here?" she asked with a smile.

Gere smiled and mumbled, "All the free meals."

"There's Leonard Bernstein," said special assistant to the president Jim Free, popping on a pair of tortoise-shell glasses as Bernstein walked by. "Politicians love to look at movie stars."

Free was optimistic about the chances for his doing some more movie star watching in the Republican White House. "I might get invited back," he said. "I see a lot of Republicans here."

And apparently the movie stars were rather curious about the politicians. That's the wonderful thing about Washington. It gives everyone a chance to look up to someone else," said Defense Secretary Harold Brown, who had met with the president earlier in the day on the issue of Poland.

Leonard Bernstein, standing in a corner with friends and his daughter, Nina, was tellng a story about his day at the White House. After an emotional afternoon, Berstein said that Rosalyn Carter suggested he rest up in the Lincoln bedroom. "I laid down on Lincoln's bed," he said. "That's the room where the Emancipation Proclamation was signed." His eyes filled with tears as he spoke. After the reception, Bernstein said he was going back to the Lincoln bedroom with his three children and his mother to light a menorah.

One star -- though not from the realm of movies -- was Walter Cronkite, who had his own fans around. "Everyone's asking me about my retirement," he said. "I'm getting so tired of hearing about it that I may have to not do it." He grinned. "I'm going to be around. I'm not going into seclusion."

Lillian Gish was sitting on a plush sofa, greeting others who came up to her. "You're superb, just superb, dear," said Gish to Lauren Bacall.

"Well, thank you," said Bacall. "Were you here last year?" Gish asked Bacall. Upon hearing the answer was no, Gish said, "Oh, they like new talent."

Meanwhile, actress Maureen Stapleton was admiring Bacall's slinky low-cut glittery gold top. "Looks very well on her," said Stapleton, nodding, "considering she borrowed it from me," Stapleton turned to Bacall and said, "I want it back Monday dry-cleaned. No, you'll probably sweat. Keep it."

"She just looked so beautiful," said Stapleton, explaining the joke. "You can't look at her without saying something."

Just then, Jim Frazier, Lillian Gish's manager, rushed up behind Stapleton and cooed, "I loved your movies."

"Go ---- yourself," said Stapleton good-naturedly.

"All two of them," Frazier continued.

Meanwhile, Washington lawyer Clark Clifford was beaming upon seeing Maureen Stapleton. Stapleton smiled back. "I guess I know him from somewhere," she said, going over to introduce herself.

Treasury Secretary G. William Miller entered late and joined the mammoth reception line. He said he is a great fan of Cagney's. "He's an old acquaintance of mine. He used to have a house on Martha's Vineyard, near the house of some friends of mine. We used to see him all the time."

Standing near the buffet was Catherine Basie, wife of Count Basie, whose orchestra would be playing later. "We made him lie down back at the hotel," said Mrs. Basie of her husband. "We told him we'd be right back."

Jon Hendricks, the jazz singer, stood by the lobster and said he would be singing with Basie later on. What are you going to sing, he was asked. "Whatever he wants. You know that one?"

As guests were leaving for the Kennedy Center, the band struck up "People Will Say We're in Love." Laureen Bacall went dancing out the door of the White House singing along, when suddenly the pure high notes of Leontyne Price peeled through the foyer and out into the cold night air.

At the Kennedy Center Jamie Berstein, daughter of the composer and an aspiring singer, had sung for her father from the Opera House stage. Afterward, she was ecstatic. "I thought I wouldn't be able to see him," she said. "There was a spotlight in my face, but I could see him! We had a lot of eye contact. But I couldn't look at him too much -- it was too intense."

Dancer and choreographer Edward Villella watched the evening progress with satisfaction. "These things get better and better. Cagney's contribution to American dance is a great one. Look at the great choreographers of today -- Balanchine and Robbins -- they look for style. The Cagneys and the Astaires have given us an American style -- the attack, the sharpness, a linear quality," said Villella with flair, to the obvious pleasure of the three women standing with him.

Art Gorman, Cagney's Marine escort for the evening, was equally enthralled with Hollywood's veteran tough guy. "He doesn't dance up the walls anymore," Gorman said. "But he's sharp as a tack."

And standing in the middle of the room was George Stevens Jr., producer of the show, receiving accollades for the gala from such notables as Douglas Fairbanks Jr. Stevens smiled contentedly, holding a glass of red wine. "I feel awfully good," he said.

And of course so did Roger Stevens, chairman of the Kennedy Center. He said he'd never even seen a Jimmy Cagney movie until he saw the film clips at the gala. He plans on going to see some now.