There is a certain kind of well-heeled Manhattan woman who would expire before walking into the cool recesses of 21 in anything but a little silk dress and pearls -- but Jackie Collins, the flash and trash queen of the paperback scene, will have none of that. She arrives at Twenty-One in skin-tight black jeans, black T-shirt, and a broad-shouldered suede jacket with leopard-skin insets jagged as lightning, sending shock waves from shoulder to bust. Kaaaaa-boom! Kaaaaa-boom!

Came in on the Concorde the day before yesterday, she says, and she is exhausted -- pay attention to brand names, darling, this is a story about Hollywood. As in "Hollywood Wives," Collins' maybe-it's-fiction, maybe-it-ain't tale about the rich ladies of West Los Angeles. And don't pretend you've never heard of it. If the paperback has hit No. 1 on the best-seller list in New York and London, someone must be reading it, no?

My God, the week it came out -- we're talking hardback, maybe a year ago -- Sue Mengers, Sue Mengers the agent, called Collins up and she said, "Honey," she said, "Honey, Sidney Lumet just called up from New York and said, 'I didn't know you had twins' " -- thinking it was her, you know, a reference to the book -- and said, "I'm sending my husband out for it now."

The week or maybe the month it came out, Kirk Douglas, running into Collins and a bunch of the ladies at Ma Maison in L.A., came over and said, "Jackie, when are you going to write a book about me?" and as one, everybody said, "But she has."

Not that Sue Mengers, Collins wants you to know, is the model for the agent in the book. Not that Veronique Peck -- who everybody seems to think is the model for the social lioness of Hollywood -- or Kirk Douglas are the people it's based on, either.

"I think it's too boring if you take somebody who's too recognizable, like Sinatra -- you know what's going to happen, and that's boring," she says. "What I've tried to do is capture the essences. The aging movie star, the stars with the really big names . . ."

A fast smile and a naughty admission.

"The producer, I did base on one specific producer. He's alive and well and he knows who he is . . ."

Haha. Oh, why are they seating us upstairs? They'll be sorry. We'll do a Jackie and call it "Club Twenty-Two." Let's get the waiter right away and order. Why did you say Hollywood Wives like this restaurant? Let's get our lettuce leaves. Then we'll talk.

Here's a sentence from the book: "Elaine Conti awoke in her luxurious bed in her luxurious Beverly Hills mansion, pressed a button to open the electrically controlled drapes, and was confronted by the sight of a young man in a white T-shirt and dirty jeans ----ing a perfect arc into her mosaic-tiled swimming pool."

Even People magazine called it "smarmy." Though as we mentioned, somebody out there is reading it. The hardback was 28 weeks on the New York Times best-seller list. Two weeks after coming out in paperback, there it was at No. 1. And this has been happening for eons now. Her very first book, "The World Is Full of Married Men," published in England in 1968, was a best seller the moment it hit. Did we mention that whenever Collins finishes a book (there have been nine now) she buys herself a little present, like that leopard-skin number ($800) she is wearing? That ring on your left hand, by the way, Jackie -- can you lift your wrist to show it to us or shall we have the waiter run out for a crane? -- that's a rather serious bit of stone. Another little present? Oh, your engagement ring? From your first husband? Well then, dear, why didn't you give it back?

The sort of reply you'd expect from someone whose sister is a star on "Dynasty" -- half satiric, half fact.

"Because I married him. You don't ask for the engagement ring back after you've married somebody."

She's a good-sized woman. Long hair, long nails, long legs, the kind of body that seems not so much wrapped in her T-shirt and jeans as packed. The down-to-earth, seen-it-all air of a woman who would be unperturbed were a guest to get sick on the floor. Savvy. Direct to a point. Perennially amused. Born in London to a theatrical family, shipped off to Hollywood to live with older sister Joan Collins when she was booted out of school at age 15. The sort of woman who while telling you of her early actress days in Hollywood and her "schoolgirl fling" with Brando says wickedly, as to the time of the affair, "before he got fat." The sort who says of her sister's tell-all memoirs, "She has the worst memory in the world. I read it. I didn't recognize anybody."

As for her own book, and her own self, no, no, no -- though she divides her time between London and Los Angeles, she could never be a Hollywood Wife.

For one thing, a Hollywood Wife is totally dependent on her husband's status, her husband's money, and Collins, whose husband -- present husband -- owns the London discothe que Tramps, makes her own money, she says. For another thing, Hollywood Wives spend lots of money on clothes or getting their nails wrapped, and her outfit -- with the exception of the jacket and that ring -- is "probably under $20," she says.

"A Hollywood Wife wears silk dresses and designer clothes and has her hair and nails done. I usually do my hair myself -- though the other day I went out to have it cut and didn't get out for three hours," Collins says. "There were women there having their makeup done to go out with the girls . . . Hollywood Wives are busy. They're busy getting themselves together, they're busy going out to lunch, they're terribly busy women . . .

"I know women like that," she says in her brisk British accent. "And there's nothing wrong with them, except that they live their lives in a vacuum. They actually say things like, 'I need a new dress to wear for the party,' and you say to them, 'But you spent $4,000 for a dress last week,' and they say, 'But I need it.' I know one woman who says, 'Honey, my Rolls gets to the edge of Beverly Hills and automatically turns around and comes home.' "

She warms to her subject.

"The woman threw a party for her husband -- they've been married for 20 years and outside of their wonderful house, wonderful marriage, her husband has -----ed everything that moves for 20 years," Collins says, "so she decided to have a big anniversary party and she invited everything that moved for 20 years and he had -----ed for 20 years. They all walked into the party, every woman, or all the ones she could get ahold of . . ."

Oh, how wonderful/horrible! When was this party? Did she go?

"Well, I didn't. I was in London, unfortunately, but it was a couple of weeks ago," she says. "But I have a lot of friends who tell me things. I really wouldn't have to put a foot out of my house."

"One thing I'll always remember, and baby, never will I forget it, there has never been anyone else who did it for me the way you did. You feel the same, don't you?" That's just another one of those sentences she writes. Just thought we'd throw it in while she was ordering.

Did we tell you about her childhood, by the way? Daddy, the theatrical agent; Mummy, "extremely feminine, wonderful"; one brother; Joan, the older sister; Jackie, the wild child who was told she was pretty enough to be an actress but never encouraged to do anything as mental as write. Joan, in her book -- "Past Imperfect," also a best seller -- whined and carried on something awful about the remoteness of Daddy, but that is not Jackie's recollection.

"Joan seems to have this incredible hang-up about him," she says. "He was strict and he was a chauvinist and my mother let him get away with murder, but I didn't see him as terribly remote. He is a terrible chauvinist. He goes around saying he would never read my books because they're filthy. . .' "

Sister dearest is six years older, is it?

"It depends what the newspapers are making her at the time," says naughty Jackie. "I'm 42."

The newspapers say Joan is 50.

"She's around that," Jackie says.

She cut classes, bought wicked Frank Harris books in Olympia Press editions when she and Mummy went on vacation in the south of France, started writing but never finished perfect copies of Mickey Spillane and Harold Robbins while in school. "Yes," with a giggle, "I loved flash and trash even then." At 15 to Hollywood, at 18 back to England and marriage to a man in the clothing business. "He was a Jewish Prince. I think I married him because everybody said I couldn't -- that he wouldn't want to marry me," she amends. Tragic marriage. No, really.

"He was, um, actually very sick," Collins says. "He was, um, a manic-depressive -- a fabulous person, but he was put on drugs . . . Methedrine, for the depression, and then one year the doctor went on vacation and said, 'Why don't you just administer it to yourself?' which was essentially the end of him."

One child. Divorce. They found her husband dead in the car shortly after that. Overdose, Collins has always thought. There were, anyway, some very iffy times, and she will always remember fondly her ex-brother-in-law, Anthony Newley, for the time she needed money and he gave her, without asking, l,000 just like that. She remarried at 24, had two more children, acted a bit. The last role she remembers was in an episode of "The Saint," with Roger Moore, sitting in the car necking when Roger's wife arrives screaming, "Roger, who this woman?" Wonderful, terrific, volatile woman -- one of her best friends -- and yes, the necking was in the script. She was playing a movie star. She had a tendency to play either movie stars or Italians. It was the period when English actresses were all supposed to look like Julie Andrews, and she (giggle) was "slightly voluptuous."

The first book came out of a party. "The world is full of married men," a woman said quite cheerfully, and there it was, full sprung, the title. It wasn't so hard to start -- Collins had always been on the sidelines looking -- and this time she had someone, her second husband, encouraging her to finish. She wrote a "different kind of book" than was being written at the time, a book that said "if a married man can play around in marriage, a woman can, too."

"The women who were writing at the time, Edna O'Brien, Penelope Mortimer, were all writing about women going off to the country and having nervous breakdowns over married men," she says. "I was writing a woman who was not in literature at the time."

She sent it to a publisher without an agent. Within a week of publication it was on the best-seller list. Others followed. Oh, yes, she knows some people think they're trash, because people "skirt around the edges . . . don't know how quite to say it, and finally say, 'Wouldn't you like, um, to write a better book?' "

She does not.

"I'm writing what I do to the best of my ability, and I love what I write," she says. "I picked up a book I wrote in l969 -- 'The Stud,' it was about a guy who has a club and is used by women when he thinks he is really using them -- and I thought, 'This really is a book about 1969. I captured a little piece of 1969.' "

The thing is, she has this knack, you know. She can be sitting there at a party, or in a restaurant, and see a person and just "psyche into their lives." Also, she has the eye.

"I saw this conversation between an actress and a producer," Collins says, sliding out of a discussion about how she does not have live-in help at her house. "It was really a boring conversation -- I could see how they were boring each other -- and suddenly the subject of maids came up. And they really got animated. She was saying, 'Do you know my maid brought in the clothes the other day on a wire hanger and hung them in my closet?' and he was saying, 'Godamighty, Godamighty, you won't believe what mine did -- she ironed my shirts with the wrong iron.' I was sitting there saying to myself, 'I don't believe this. I just don't believe this.'"

"I have a theory," Collins says over her salad. "I think that somebody like John Irving writes the real truth and all the rest of us write watered-down versions. People walking around in bearskins, that's real life -- you can walk down the streets of New York and meet people from John Irving's books. If I put in any of my cast of characters, people wouldn't believe it. It's too cliche'd -- the gold chains, the hair transplant, the fake suntan because they don't want the sun to ruin their skin . . . I'll tell you something, in 'Hollywood Wives' I have toned the stories down . . ."

No, no dessert, waiter. Tell, Jackie darling.

"Well, this is one I've told before," she says, "but I went to a huge Hollywood party recently where I couldn't get into the loo because everyone was snorting cocaine, and I was sitting at the bar -- I love sitting at the bar -- and watching several movie stars passing a nubile young 19-year-old movie actress one to one . . . Well, they were just dancing, but you could see what was eventually going to take place."

Awful. Disgusting. Tell another.

"Well, I told you my vasectomy story . . . No? I guess I must have told it to Regis Philbin on 'Good Morning, New York.' There is one couple, genuine Hollywood Royalty -- everyone treats them beautifully though he's carrying on all the time -- and one morning a girl comes to the door and says to the wife, 'I'm pregnant by your husband.' It turned out to be a false alarm, but the wife simmered for two weeks and then she said to her husband, 'You're looking awfully run down. I've made an appointment for you to get some Vitamin B-l2 shots,' and when he gets there she had arranged for him to have a vasectomy and he went through with it. He can do whatever he wants, she doesn't have to worry about another girl turning up at the door. And that's an absolutely true story."

How does she know?

"I do what you do," Collins says, "get three sources . . ."

One more, please.

"Well," she says, not pausing an instant, "there was this husband -----ing around on his wife. And he had this girlfriend whose birthday was coming up and he didn't want to spring for a present so he went to his safe deposit box where his wife kept her jewelry. And he saw a ring his wife hadn't worn for a long time and he thought, 'Well, she'll never miss it,' and he took it and gave it to the girlfriend and said, 'My darling, this was my grandmother's.' And the busty trollop puts it on and says, 'How wonderful' . . .

"Three months go by and the wife finds out about the affair and she determines to face the girl and she goes to her apartment and the girl comes out and they have a screaming row. The wife is screaming, the girl is screaming, the girl says, 'I don't know how you can accuse me of those horrible things . . .' She's weeping. And as she's weeping she puts her hand to her eyes -- like this -- and she's wearing the ring. And the wife says, 'Where did you get that?' And the girl says, "Your husband gave it to me. It. Was. His. Grandmother's."

Collins is choking with laughter.

"Well, you know, they ended up the best of friends, getting drunk, and going over and beating up the husband . . ."

No!

"Driving over in matching Mercedes and beating the hell out of him . . . three years ago."

How does she know?

Triumphant look.

"I know the wife. I got it from the horse's mouth, you might say."