She is wearing an olive-colored suit; and her hair is a blond thicket bound around her head with yellow butterfly clips, and her blue eyes are direct, and faraway, too. And she has freckles.

Close to her, she holds her month-old daughter, Gracie, swaddled in a shawl, and she says, "She's not very pretty at the moment. She has baby acne. She's really a sweetie. She's much more sensitive than my other kids, more sensitive to touch and noise. Yeah, I sort of felt, 'Well, this is my third, I can just glide along with this one, I'm a pro.' Meanwhile, this one is so skittish. She's like a pixie."

Not skittishly, Gracie sleeps.

Later she says: "You know, you're supposed to be able to handle everything, but there are some things that are just much bigger than you are. Life forces and things."

And there is Gracie, still asleep, wrapped in alpaca and mother, in the cool and quiet of this room.

That image, and the feel and sound of it, and the seeming ordinariness of it, touches you in the same way her new film, "Heartburn," touches you, or "Sophie's Choice," or "Kramer vs. Kramer," or "Plenty" -- you feel that Meryl Streep, simply with her presence, is telling you the truth, not just about her life, but about your own.

"Directing Meryl Streep," says Mike Nichols, who has done so twice, once in "Silkwood" and now in "Heartburn," "is so much like falling in love that it has the characteristics of a time which you remember as magical and creative and of which you're extraordinarily grateful, but which is shrouded in mystery. I don't remember the things that she said and that I said."

What does this private glimpse of Meryl Streep have to do with acting? Everything.

"What we see on the screen," says Nichols, "is the actor's nature, the actor's essence."

"I used to have a little thing that I said to myself early on, when I was in 'Deer Hunter,' " Streep says. "I just didn't know how to be, y'know? When I'd finally get there, I'd feel too small to fill the space needed, or there was too much, much too much, and I just had to fit it into a small place.

"So I was just casting around for anything to get me through, and this little thing that I've used all the way through came to me. I say to myself, 'Be who you are and know what you know, and that's all you have to do. That's the entire job.' Suddenly I became potent. Oh! it sounds completely simple-minded. I told it to somebody else, another actor who was in terrible trouble, and he said, 'What the hell does that mean?' But that's all I'm doing, really."

Because an actor's most precious asset is his very nature, he has to fight to protect it. Different actors work differently.

"You get to a certain point in your life," Streep says, "and a certain amount of accomplishment and fame and notoriety on the streets of New York City, and certain people are gunning for you for that reason, other people are more willing to like you than they should be. I have to insulate myself from all that stuff, I have to get away from it. I have to really hide out and keep myself safe from whatever the evil forces are."

"I really admire these people who are right out there, like Jack Nicholson or Mike Nichols , and it doesn't inhibit them from observing or participating. They keep their pores open to experience. They're both sort of hungry all the time for experience and people; they devour people, events, the hurly-burly of New York, all that stuff. Los Angeles. I'm really impressed by that! I can't do it."

Thus the paradox for the actor, for whom the personal and the professional are like different tides of the same ocean. "I know that when I was in drama school," says Streep, "the big thing was how to cry. You get to a certain point in a play and you're supposed to break down in tears. And I remember when I first came to New York I saw Irene Worth in 'Sweet Bird of Youth ,' and I went back and just kvelled, I made a fool of myself. I said, 'I don't know, I just think you're the greatest actress I ever saw!' I said, 'But you know, how do you cry like that?'

"And she said, 'How can you not?' And writ in the lines on her face and in her experience . . . And you thought, the world as it is . . . Yes, there's something to living."

An actor is working as long as he's alive, and touched by the events of his life. "You just get more stuff, you just have more stuff each day," Streep says quietly. "Good and bad."

Some Incidental Facts About Meryl Streep

1) "Meryl" is a corruption of "Mary Louise," her given name.

2) She grew up in Summit, N.J., a comfortable suburb of New York.

3) Her father Harry Streep was an executive for Merck and Co. pharmaceuticals.

4) In high school, she was homecoming queen.

5) She graduated from Vassar College and the Yale School of Drama.

6) She was introduced to her husband, sculptor Don Gummer, by her brother, dancer Harry Streep III, whom she calls Third. They were married in 1978 and have three children: Henry, 6, whom she calls Gippy; Mary Willa, 2, whom she calls Willa; and Grace, born in May, whom she calls Gracie.

*7) She has been nominated for six Academy Awards and has won two: for "Kramer vs. Kramer," Best Supporting Actress; for "Sophie's Choice," Best Actress.

"We live in a society that cherishes spontaneity to such an extent," says Alan Pakula, who directed Streep in "Sophie's Choice," "that skill is thought of as second-rate."

But once you've got past the genius part, skill is everything for an actor. In which regard Meryl Streep, at 37, is partway through a project so ambitious as to be mind boggling, for what she's doing is creating a new person every time out, from Sophie of "Sophie's Choice," a Polish e'migre' wounded by history, to Susan of "Plenty," a former British spy wounded by her own exaggerated hopes for life; from the randy nuclear activist Karen Silkwood to the repressed writer and adventuress Karen Blixen. She's doing the kind of character work that you associate with an Alec Guinness, while retaining that elusive, romantic quality you associate with a movie star, that ability to move and enchant us.

"It probably has to do with my world view," says Streep, "which is that everybody's different, but they're all the same in some way. I just like to investigate all these different people to see what the commonality is with me. When I start with the script and I read their story, I hear the 'Ping!' that makes a connection with my own life or experience. But it's also the thing that makes me see where all these different people link up.

"It tickled me to be Baroness von Blixen in these $500 riding boots in Africa reading the script for 'Heartburn' about this woman who's schlepping two suitcases, a baby and a stroller through the airport. I completely understood that woman as well as I felt I understood some parts of Karen Blixen. It's heartening to me, it's heartening to be embarked on this look at all these different women. That's my secret pleasure in it."

*Yet the irony of Meryl Streep's career is that it is precisely her skill that has led to a backlash against her. Her critics have charged that she always seems to be watching herself in the mirror, that her performances are too "worked out," that you can see the machinery working. It's as if we're so used to dividing performers into movie stars, who grab us with an expression of personality, and character actors, who play a role, that we persist in believing that someone like Meryl Streep simply can't exist.

"I've been trying to think about writing about acting because nobody really writes about it, especially lately," she says. "It's not popular to think about as a thing that can be written about, and there's a part of me that agrees with that. There's so little magic left in the world -- why not preserve whatever mystery there is that exists? And I always feel when I watch people act, whose work I love, that I don't know how they do it.

"It probably has something to do with the loss of these icons of the '30s and '40s. There's still a great need to believe that you are what you represent in the films. I saw that with Jack, the way that people are on the street with him. 'Aaaaaaay, wick-ed!' You know, that kind of thing. They want to think he's that way."

An actor's palette consists of his voice, his face, and his body -- the way he moves -- and in the case of Meryl Streep, you're struck first by her exquisite ear. Not only the accents, but the intonations and rhythms, and even the timbre of her voice, change from role to role, so that she captures not just a way of speaking, but a way of thinking that the speech reflects.

"In 'Sophie's Choice,' " says Nichols, who was born in Germany and whose first language is German, "Meryl spoke perfect German, with only a trace of a Polish accent, very fast. Now that's not supposed to be possible. But it's no different from what she's doing in all these parts. She has the absolutely specific, accurate sound of a person from that particular place of origin."

In "Plenty," her voice evoked a species of shrill craziness that is peculiarly British; in "Out of Africa," her voice, besides carrying an impeccable Danish accent, became an expression of the process of aging. And for "Heartburn's" Rachel, it means talk that is, in some undefinable sense, identifiably Jewish.

She created Rachel, she says, by assembling a mosaic of people she's known. "They're friends of mine. I don't think anybody would ever be a friend of mine if they knew how many times I'd used them. Jewish girls I know, city-bred girls. People with a certain amount of savvy, that only people who were born here and brought up here have. And I stole things from Nora screen writer Ephron that were just patently obvious, like her glasses. Her terrible posture. I tried to get as thin as she was but I never could," she says, and laughs. "That always . . . pleased her.

"It's probably more of a city thing, too," she says, of the quality she caught in Rachel. "Although that's not true, it's not true. My friends that I drew on for this, two of them are from suburbs, and two of them are from here. But they all act exactly alike in a certain way." And she laughs again. "Cracks me up! In certain circumstances.

"You're not allowed to talk about certain things like that. Like you're not allowed to say you can recognize a black voice on the phone, but you can tell. I don't know why that's against the law, it's stupid."

Streep's style, though, goes beyond her voice, to the expression on her face, and when it's expressive and when it isn't; to the way she carries herself, and the way she moves. In "Silkwood," she's all jut and angles; in "Kramer," stiff and tentative; in "Plenty," sinuous and loose-limbed, and graceful as a bird.

She brings such a wealth of detail to her roles that the convincing expression of emotion -- which is hard enough -- is turned into a way of realizing a character.

"When we were working on 'Heartburn,' " says Nichols, "I would see her fall onto her knees with the drawer with the evidence of her husband's infidelity -- weeping, whining, completely naked emotionally -- and I would think, 'That's the real Meryl, that's Meryl exposing her heart.' And in the middle of working on the rough cut, I saw 'Out of Africa.' When she received the news of Finch-Hatton's death with this barely perceptible tremor in her cigarette hand, and went back to reading, I thought, 'No, that's the real Meryl.' The truth is that it's all the real Meryl, and she can actually change herself within."

All of which must go on in the midst of a crew of a hundred, and with a camera and a lighting design that restrict you, and other actors to play against.

As in, for example, this deceptively simple scene from "Heartburn," in which Rachel, pregnant with her second child, feeds her daughter and asks her father's maid if she'll take care of her for the day.

"So I was, uh, shoving this food in the baby," Streep recounts. "There's always twins, because of child labor laws. They set it up as one child, and then they bring the other one in, who knows absolutely nothing of what's going on. It was a nightmare, frankly.

"In a movie like this, which is colloquial, everyday -- we all get lazy. It's like rolling out of bed, going to work, that kind of thing. This really pulls all your technique together, because a child will only do it on one take, just once. They'll do it 150 times, wrong, or the camera won't be able to follow what they do.

"So you have to be great, or at least remember your lines, on every single take. That's what I was thinking of when I was doing that scene -- remembering my lines," she says, laughing. "I remember Sigourney Weaver did a play at Yale, and she kept going, 'Is there a space between my eyebrows? Is there a space between my eyebrows?' That's the way I felt, like there was just one line, like this," she says, drawing a line with a finger across her brow, "because you're concentrating so hard. That's actually the way I go around most of the time when I'm with my children."

Yet there was something in that scene that goes beyond technique. Like much of "Heartburn," a movie where character is plot, and everything happens between the lines, the surface has nothing to do with what's really going on. The chatter hides the crisis of a woman whose world has just fallen to pieces, and who is trying to figure out how to put it back together.

"It's very complicated, that whole thing," says Streep. "It's about this mess that your life turns into when you let down your guard and let yourself be loved, or imagine that you are, and then whammo. But as high as your rage is, you still don't want to leave. That's a terrible position to be put in. Back and forth. It's all about trust and loss of trust. Once that's gone it's really, I think, irredeemable or something. You can't get that back."

Amidst all the technique, what remains elusive about Meryl Streep's acting is a resonance that even directors who have worked with her find mysterious.

"If there is a character and there is a critical moment, and in that moment there are seven different emotions, a very good actor will show you all seven emotions," says "Kramer" director Robert Benton. "A great actor will show you one or two of those emotions, and the blank spaces you will fill in, like a Matisse drawing. The greatest actor will show you that in fact it was not at all the emotion that you expected, but something else that so illuminates the moment that you find out something not only about the character, but about yourself, and life. And that's what Meryl does."

"It's completely mysterious to me, for instance," says Nichols, "that weeks before we start shooting, the company begins to get together. And whoever is playing her lover is in love with her, and whoever is playing the villain is a little scared of her, and whoever is playing her best friend is her best friend. She shifts her soul slightly and I don't know that there's ever been anyone who ever worked in films who's ever done it quite that way."

"The whole notion of being pregnant and with a little child and being in that kind of trouble in your marriage is so charged," Streep says of her role in "Heartburn." "I felt that vulnerability that you can have in a pregnancy; it's pretty amazing. You really let down your guard and you sort of have this tacit agreement with your husband not to let certain things count, like how pretty you are. You know, for a certain amount of time, he's just gotta bear with me here, this is the way it looks. And with that letting down your guard you really let the doors open. For somebody to be unfaithful is tough, but in that time . . . I would have been just jelly. So I had a feeling for what that would be like. It upset me every time I thought about it, so it wasn't that hard to imagine."

Two of Streep's early roles involved women who gave up their children -- Joanna Kramer, who simply couldn't cope, and Sophie, whose "choice" was to keep one child at the expense of sacrificing the other.

"Probably if I did 'Kramer' now it'd look completely different," she says. "Ah, I dunno, I'm not sure in what way. Although the woman is unformed, that's sort of the point about her. She has the sense to know that. But yes, that's what I feel about it when I look at it now. Unformed. Look, all I can say is I'm glad I didn't have to play that part having children. I didn't have any kids then. I don't think I could have looked at the situation in any professional way. I wouldn't have been able to function, imagining that.

"When I did 'Sophie's Choice,' I had one child. I knew that the 'choice' was coming, I knew that that was what the movie was about, I knew that that was what the book was about. Although I never read it in the book, I skipped over those pages, and when I would go over the script, I just skipped over those pages, I never looked at it. I looked at the German, somebody told me what I had to say in German, because I just didn't want to think about that part."

Gracie snoozes in her shawl, and with the child in her arms, she is a mother, and with her giggles, sweet sixteen; with her wise eyes, an old woman, and with her emotional nakedness, a kind of rare child "able," says Nichols, "to walk through any crowd, any situation, right up to you, look you right in the eye, and be right there with you, and deal with anyone or anything." She is simply Meryl Streep, and God only knows what that means.