Monday night. On the street, at 52nd and Fifth, a bad cornet player is playing "New York, New York" into the hot dirty night air.

Al Pacino walks into the closest building, past a mob of photographers, through a solar flare of flashbulbs, and into an elevator. It's going up, up in Olympic Towers -- part of the new high-ritz hierarchy -- to the 21st floor. He's in a brown, three-piece suit, and the sound of the yelling photographers seems to hang in the small car going up the shaft. "Al!" they were yelling, "just a smile, Al! Look surprised!" Al Pacino looks at the floor of the elevator. He doesn't have very far to look. "I give up," he says. "What a game" . . . 15, 16, 17. . . . "I used to try and get around them" . . . 18, 19, 20. . . . "Now I just give in" . . . 21. The doors open. A phalanx of photographers is waiting. "Al," they yell. "Just a smile! Look surprised!"

Al Pacino walks down a long corridor of mirrors, past bartenders, and reporters, and movie stars, more stars than could fill the head of the Statue of Liberty. John Belushi, solid as an alphabet block, is wearing black evening clothes that make him look like a mutton-eating 19th-century mayor of New York. Richard Thomas, disjointing his limbs like a balletic contortionist, dances with Swoozie Kurtz. Brooke Adams, held together with something like parachute nylon, giggles with two young men. Amy Irving, looking through eyes ancient and deep, stands silently as a cat from the Tutankhamen exhibit. A Halston model named Pat Cleveland in a long,beaded flapper gown is dancing maniacally, jumping up and down, hurling her brown mane around like an industrial mop in rotation.

Pacino walks into a huge room, maybe 80 by 20 feet, entirely dominated by glass. Massive 15-foot-high windows opening the room to the city sky are interrupted only by great mirror sections covering the walls.

This is Halston's house. A tall, elegant designer of women's clothing who occasionally endorses synthetic fabrics on television, Halston once allowed his apartment to be photographed by Life. Tonight, he is giving a party for Liza Minnelli and the opening of the uncut version of "New York, New York," the movie she made with Martin Scorsese in 1977. Halston has filled his home with a couple of hundred people, a quarter of whom are so well known that you would recognize them if their faces were on the radio. Pacino is on home ground.

He looks up through the mob and smiles with the face of a boy who has just gotten off the bus at summer camp and sees last year's bunkmates. "Hi!" says Liza Minnelli. "Hi!" says Marty Scorsese, sitting next to her on a couch. "Hi!" says Bobby De Niro, the third bunkmate sitting against a window so huge and clean that it gives no evidence the three kids won't tumble backwards toward the St. Patrick's Cathedral spires next door. "Hi!" says Al Pacino and goes to sit down with his happy friends on the couch.

De Niro, fluffy as an Easter chick in a blow-dry cut for his new Scorsese movie, "The King of Comedy," edges off the couch and leans into a long, silent communication with a TV newsman who's brought his crew up to broadcast the mob. Scorsese, tiny and condensed as heavy hydrogen, sits in a white dinner jacket with a short Prussian army crewcut and clipped beard, looking somewhere between Montgomery Clift as Freud and "Heart of Darkness." He's jabbing his finger into the night and talking very fast, Mailer-like, filling the cigarette smoke in front of him with images that Liza Minnelli seems to be reading.

Halston stands watch over it all -- this party of his. He looks sleek and lean, minor royalty with tremendous resources, carrying something of Prince Philip and a bolero dancer at the same time. He scans his dukedom with imperious deliberation, and when the dance tape goes up awfully loud, his eyes widen, his mouth tightens and he notices that Liza can't exactly hear herself speak.

"The music," he says softly, with a velvet sledge. The music goes down. Liza hears herself.

Scorsese hops up and shoots across the room, jutting his finger harder into the air, throwing his Gatling-gun word-bullets through the room, calling straight up into a film critic's bow tie. There's something demoniac there, all right, and you can see that whatever power turned "New York, New York" into a work of flawed brilliance comes out of Scorsese and can hardly hide itself.

Most of the crowd at the party had moved over to Halston's glass paradise from a screening of the picture that failed so badly the first time around. It was a dark, scary homage when it came out, explosive and emotionally combative, a genuine musical noir -- all singing, all dancing, all psycho. It was also one of the best diagrams of postwar cultural transitions -- in its colors and its shapes and its sounds -- made about America during the '40s and '50s. It was so threatening and tense, it became hard to watch, almost impossible to see a second time with its rage and suppressed combustibility and its hard diagnosis of the culture.

Scorsese had filmed a number for the picture that was rumored to be one of the best musical scenes ever shot. It extracted the best and the dopiest of American musicals made between 1945 and 1955 by MGM (with the exception of "A Star Is Born," whose classic look pervades "New York, New York," and which was made by George Cukor for Warner Brothers). When the picture ran long, Scorsese -- with a perverse dramatic defiance -- pulled the "happy endings" number and also pulled the plug on his picture, turning it into a dark, severe drama. This year, Scorsese got the money to return the footage to his musical, and suddenly "New York, New York" -- no longer enigmatic and scarred -- became a fully comprehensible, flawed classic of the screen. Still too hot and still too cold, the picture nevertheless is finally complete and says exactly what its director wanted it to say, graphing the rage that sublimated itself in movies and music after the war.

De Niro and Scorsese, it had been said, had walled themselves up watching kinescopes of Sid Caesar and the old "Your Show of Shows" crew to find the chemistry for the bottled anger of "New York, New York" (just as they had been screening Jerry Lewis' "The Nutty Professor" for their new picture, "The King of Comedy"). "Wonderful, great, great stuff, Mel Brooks and that crowd," Scorsese says, looking up. "Great, great, funny stuff, they were geniuses, what a crowd." He rattles the words out and somebody walks in front of him, lunging in for a kiss. "It's complicated, very, very complicated," he pecks at the word. "Hard to talk about, I can't get into it, you know . . ." (somebody kisses him) ". . . here."

Lauren Bacall sits smoking like mad with Harry Guardino, who looks something like Jason Robards tonight. Mikhail Baryshnikov, miniaturized and beautiful, like something you might want to put on the shelf, goes over to Liza in his '20s tuxedo, chain-smoking as well, smiling slightly through his beautiful stuffed-leopard eyes (what taxidermist wouldn't give it all up for him?). Pat Cleveland, the Halston model in the long, beaded flapper gown, dances on maniacally, her long bare legs going, going, going, jutting back and forth, never stopping -- making the women at Gatsby parties look like narcoleptics.

Another pair of legs walks past hers, ambling slowly, definitely, over to the band. They are a little shorter than Pat Cleveland's legs (so are almost everybody's but Halston's) but they are strong and on their way, and they are slicing out of a short miniskirt of ruby-slipper material.

They belong to Liza Minnelli, who stands with the band, her back to the crowd. She talks to the musicians quietly, bent over, laughing a little. Pat Cleveland keeps jumping. The music stops. Pat Cleveland keeps jumping, but the crowd like a tide moves up to the edge of the dance floor, lapping at its edge. There is a row of people facing Liza -- Baryshnikov and John Belushi and Ann Miller and Treat Williams -- all of them. It's exactly like the movie! Liza puts her hand up, and they wall around her until they're as even as the Yankee Stadium outfield fence, standing and waiting for her. And she opens her mouth and sings "Our love Is Here to Stay," and raises her voice up into a jazz glissando, and pipes her thank-you note to the glassy Halston, who stands and watches his guest of honor without even a small chip in his semiregal face.

And when it's over, there are roars and yells and a great deal of human worship among the stars on the 21st floor of the Olympic Towers. Someone yells "Sing 'Lucky Star,' " and Liza asks " 'Lucky Star'?" and then somebody else yells "Newy, Newy, for Halston!" Liza gives her patented throaty giggle and says, as the arrangement for the doo-dee-dooty-doo, doo-dee-dooty-doo begins to come up, "Thank you, Frank Sinatra," and the crowd laughs. And then she goes into it, kicking her legs further, walking back and forth with the chaste grace of an indoctrinated superstar, and opening her mouth to sing, "Start Spreadin' the News/I'm Leavin' Today . . ."

She goes through it but good, building and building for this small 1,600-square-foot room of 100 or 150 stars and peers and press, and somebody whispers "Gee-sus!" She does what she's been known for doing, except up close it has the power of a triple-thrust rocket, and she weaves the music up, and clocks it in with the precision of a great fighter, "New York, New Yo-ork," and for one moment you can see around the room on the faces of all of them -- stars and flacks, reporters and moguls, achievers and snobs -- a look of slight confusion and mild awe.

She's building and building, raising her hand and slamming it down, strutting the room and growling and hitting her points, scoring. They stand, watching her, and each of them around the room succumbs to it all.

"A number one/King of the Hill/A number one."

And the room is charged with the same feeling. Jaws drop and others grin, and some of the stars look down and wonder whether they're that good, and the advertising men and the TV-time buyers stand in awe of the light, and even Pat Cleveland is still for a moment in the glare of the blast, and even Halston's eyebrows are raised and Baryshnikov stops smoking for a moment. And she's singing on and on about "A Number One" and "King of the Hill"and "Top of the Heap," and there they all are, being told it about themselves and wondering whether to believe it. One of them does, and smiles. Another one doesn't and looks at the floor. And another one takes a long drag on her cigarette and looks at Liza, and having been around for a while, takes a long turn and stares out the window while Halston's people sway and whoop. Outside, up and down Fifth Avenue, only taxis and a few cars are on the street and a little boy is asleep, his head on a towel, on the steps of St. Thomas' Church at 53rd Street.

By 3 a.m. Liza gets up from a couch and disappears behind one of the mirrored doors into the morning, and Pat Cleveland, like a dolphin at play or a colt on some racetrack drug, jumps up and down until the music track ends.