On March 12, 1978, the man Meryl Streep had been dating for nearly two years died as she sat at his hospital bed. She had met John Cazale, the crane-like character actor best known for playing Fredo Corleone in the Godfather films, when they starred together in a Shakespeare in the Park production of Measure for Measure in the summer of 1976. From the beginning, they were an unusual pair: a pellucid 27-year-old beauty just a year out of the Yale School of Drama and a 41-year-old oddball with a forehead as high as a boulder and a penchant for Cuban cigars.

But the romance was tragically short-lived. Only months after she moved into his Tribeca loft, Cazale was diagnosed with advanced lung cancer. When he was cast in the Vietnam epic The Deer Hunter, Meryl joined the film, in part, just to be with him. Cazale didn’t live to see the completed work. A few weeks after he died, Meryl’s brother helped her pack up her belongings. He brought along a friend she had met once or twice—a sculptor named Don Gummer, who lived a few blocks away, in SoHo. Only weeks after losing the love of her life, she had found the second love of her life, the man who would become her husband.

It was this Meryl Streep—simultaneously grieving and infatuated, a theater actress new to movies—who got word from her agent, Sam Cohn, about a possible role in Kramer vs. Kramer, based on a novel by Avery Corman. Corman wanted to counteract the “toxic rhetoric” he had been hearing from feminists, who he felt lumped all men together as “a whole bunch of bad guys,” he says now. His protagonist was Ted Kramer, a thirtysomething workaholic New Yorker who sells ad space for men’s magazines. He has a wife, Joanna, and a little boy named Billy. In the early chapters, their marriage is portrayed as superficially content, with wells of ennui underneath.

The problem is Joanna Kramer, who finds motherhood, by and large, “boring.” She starts taking tennis lessons. Sex with Ted is mechanical. About 50 pages in, Joanna informs Ted that she’s “suffocating.” She’s leaving him, and she’s leaving Billy. (“Feminists will applaud me,” she says.) Ted overcomes his shock and gets back into the swing of single life. More important, he learns how to be a good father. It is then that Joanna does the unthinkable: she returns from California and tells Ted she wants Billy back. The ensuing custody battle, which gives the novel its title, lays bare the ugliness of divorce proceedings and the wounds they allow people to inflict on each other.

Before Kramer vs. Kramer even hit the bookstores, the manuscript fell into the hands of Richard Fischoff, a young film executive who had just accepted a job with the producer Stanley Jaffe. Ted and Joanna Kramer, Fischoff thought, were like Benjamin and Elaine in The Graduate 10 years later, after their impulsive union has collapsed from the inside. The movie would be a kind of generational marker, tracking the baby-boomers from the heedlessness of young adulthood to the angst of middle adulthood. No one was yet calling people like the Kramers “yuppies,” but their defining neuroses were already in place.

Jaffe took the novel to the director Robert Benton, best known for co-writing Bonnie and Clyde. Everyone liked the idea of a spiritual sequel to The Graduate, which meant that the one and only choice for Ted Kramer was Dustin Hoffman. Midnight Cowboy and All the President’s Men had made the 40-year-old actor the era’s antsy Everyman, but he was now at one of the lowest points of his life. Amid contentious experiences filming Straight Time and Agatha, he was mired in lawsuits and countersuits, and was in the middle of an emotional separation from his first wife, Anne Byrne.

The filmmakers offered the part of Joanna to Kate Jackson, of Charlie’s Angels. Jackson had the name recognition and the crystalline beauty that Columbia Pictures required. But Aaron Spelling wouldn’t bend the Angels production schedule, and Jackson was forced to pull out of the film kicking and screaming. According to Fischoff, the studio sent over a list of possible replacements, essentially a catalogue of the bankable female stars of the day: Ali MacGraw, Faye Dunaway, even Jane Fonda. Katharine Ross, who had played Elaine in The Graduate, was a natural contender. With The Deer Hunter still in postproduction, the name Meryl Streep meant nothing to the West Coast, apart from sounding like a Dutch pastry. But she and Benton shared an agent, and if anyone knew how to get someone into an audition room, it was Sam Cohn.

Meryl marched into the hotel suite where Hoffman, Benton, and Jaffe sat side by side. She had read Corman’s novel and found Joanna to be “an ogre, a princess, an ass,” as she put it soon after to American Film. When Dustin asked her what she thought of the story, she told him in no uncertain terms. They had the character all wrong, she insisted. Her reasons for leaving Ted are too hazy. We should understand why she comes back for custody. When she gives up Billy in the final scene, it should be for the boy’s sake, not hers. Joanna isn’t a villain; she’s a reflection of a real struggle that women are going through across the country, and the audience should feel some sympathy for her. If they wanted Meryl, they’d need to do re-writes, she later told Ms. magazine.

The trio was taken aback, mostly because they hadn’t called her in for Joanna in the first place. They were thinking of her for the minor role of Phyllis, the one-night stand. Somehow she’d gotten the wrong message. Still, she seemed to understand the character instinctively. Maybe this was their Joanna after all?

That, at least, was Meryl’s version. The story the men told was completely different. “It was, for all intents and purposes, the worst meeting anybody ever had with anybody,” Benton recalled. “She said a few things, not much. And she just listened. She was polite and nice, but it was—she was just barely there.”

When Meryl left the room, Stanley Jaffe was dumbfounded. “What is her name—Merle?” he said, thinking box office.

Benton turned to Dustin. Dustin turned to Benton. “That’s Joanna,” Dustin said. The reason was John Cazale. Dustin knew that Meryl had lost him only months earlier, and from what he saw, she was still shaken to the core. That’s what would fix the Joanna problem: an actress who could draw on a still-fresh pain, who was herself in the thick of emotional turmoil. It was Meryl’s weakness, not her strength, that convinced him.

Watch: Meryl Streep and Emily Blunt on the Movies That Make Them Laugh, Cry, and Fall in Love

Benton agreed. “There was a fragile quality she had that made us think that this was Joanna, without making her neurotic,” he said. “Meryl’s Joanna wasn’t neurotic, but she was vulnerable, frail.” According to the director, Meryl had never been considered for Phyllis. It was always for the role of Joanna.

Clearly, there was a discrepancy between what they saw and how Meryl saw herself. Was she a fearless advocate, telling three powerful men exactly what their script was missing? Or was she a basket case whose raw grief was written all over her face? Whichever Meryl Streep walked out of that hotel room, she got the part.

Darling Billy

On the first day of principal photography, everything was hushed on the Twentieth Century Fox soundstage at 54th Street and 10th Avenue in Manhattan. Benton was so anxious he could hear his stomach grumbling, which only made him more anxious, since he worried the sound might wind up in the shot.

The little boy under the covers was Justin Henry, a sweet-faced seven-year-old from Rye, New York. In her search for a kid who could play Dustin Hoffman’s son, the casting director, Shirley Rich, had looked at hundreds of boys. The blond, cherubic Justin Henry hadn’t seemed right to Dustin, who wanted a “funny-looking kid” who looked like him. But Justin’s tender, familial way with Dustin in screen tests changed his mind, along with the realization that Billy Kramer shouldn’t look like Dustin. He should look like Meryl: a constant reminder of the absent Joanna.

Getting Meryl past the studio hadn’t been easy. Some of the marketing executives at Columbia thought she wasn’t pretty enough. “They didn’t think that she was a movie star. They thought that she was a character actress,” Richard Fischoff said, describing exactly how Meryl saw herself. But she had her advocates, including Dustin Hoffman and Robert Benton, and that was enough to twist some arms.

In preparation, Meryl flipped through magazines such as Cosmopolitan and Glamour, the kind Joanna might read. (Meryl hadn’t bothered with beauty magazines since high school.) They all featured profiles of working mothers, brilliant judges who were raising five adorable children. The assumption now was that any woman could do both: the dreaded cliché of “having it all.” But what about the Joanna Kramers, who couldn’t manage either? Meryl spoke with her mother, who told her, “All my friends at one point or another wanted to throw up their hands and leave and see if there was another way of doing their lives.”

She sat in a playground in Central Park and watched the Upper East Side mothers with their perambulators, trying to outdo one another. As she soaked in the atmosphere—muted traffic noises, chirping birds—she thought about the “dilemma of how to be a woman,” she said later, “how to be a mother, all the gobbledygook about ‘finding yourself.’ ” Most of her friends were actors in their late 20s who didn’t have children, women at their peak career potential, which, paradoxically, was the height of their baby-making potential. Part of her wished she’d had kids when she was 22. By now, she’d have a seven-year-old.

She thought about Joanna Kramer—who did have a seven-year-old—who looked at those same superwomen in the magazines and felt she couldn’t hack it. “The more I thought about it,” Meryl told Newsweek after the movie came out, “the more I felt the sensual reason for Joanna’s leaving, the emotional reasons, the ones that aren’t attached to logic. Joanna’s daddy took care of her. Her college took care of her. Then Ted took care of her. Suddenly she just felt incapable of caring for herself.” In other words, she was nothing like Meryl Streep, who had always felt supremely capable.

When he first saw the set, Dustin said, “My character wouldn’t live in this apartment.” The whole thing was quickly redesigned to fit whatever was in his head. In contrast to most films, they would shoot the scenes in order, the reason being their seven-year-old co-star. To make the story real to Justin, they would tell him only what was happening that day, so he could experience it instead of acting it, which would inevitably come off as phony. His direction would be communicated solely through Dustin, as a way of bonding on-screen father and son.

On the second day, they continued shooting the opening scene, when Ted follows the hysterical Joanna into the hallway. They shot the bulk of it in the morning and, after lunch, set up for some reaction shots. Dustin and Meryl took their positions on the other side of the apartment door. Then something happened that shocked not just Meryl but everyone on set. Right before their entrance, Dustin slapped her hard across the cheek, leaving a red mark.

Benton heard the slap and saw Meryl charge into the hallway. We’re dead, he thought. The picture’s dead. She’s going to bring us up with the Screen Actors Guild. Instead, Meryl went on and acted the scene. Clutching Joanna’s trench coat, she pleaded with Ted, “Don’t make me go in there!” As far as she was concerned, she could conjure Joanna’s distress without taking a smack to the face, but Dustin had taken extra measures. And he wasn’t done.

In her last tearful moments, Joanna tells Ted that she doesn’t love him anymore, and that she’s not taking Billy with her. The cameras were set up on Meryl in the elevator, with Dustin acting his part offscreen.

Improvising his lines, Dustin delivered a slap of a different sort: outside the elevator, he started taunting Meryl about John Cazale, jabbing her with remarks about his cancer and his death. “He was goading her and provoking her,” Fischoff recalled, “using stuff that he knew about her personal life and about John to get the response that he thought she should be giving in the performance.”

Meryl, Fischoff said, went “absolutely white.” She had done her work and thought through the part. And if Dustin wanted to use Method techniques like emotional recall, he should use them on himself. Not her.

They wrapped, and Meryl left the studio in a rage. Day two, and Kramer vs. Kramer was already turning into Streep vs. Hoffman.

Dustin Time

Across a small table covered in a checkerboard cloth, Dustin Hoffman glared at Meryl Streep. The crew had taken over J.G. Melon, a burger joint at Third Avenue and 74th Street. Today’s script pages: a pivotal scene in Kramer vs. Kramer, in which Joanna informs Ted that she plans to take back their son.

The weeks had been fraught, and Benton was panicking. “I was in unfamiliar territory,” he said: no guns, no outlaws. “The suspense had simply to do with emotion, not anything physical.” Benton and his wife had planned to take their son skiing in Europe after the shoot. But two-thirds of the way through, convinced he was never going to work again, he came home and told his wife, “Cancel the trip. We need to save all the money we have.”

Dustin, meanwhile, had been driving everyone nuts. In his effort to fill every screen moment with tension, he would locate the particular vulnerability of his scene partner and exploit it. For little Justin Henry, who experienced the story day by day, Dustin’s methods elicited a child performance of uncommon nuance. Before playing a serious scene, Dustin would tell him to imagine losing his dog. For the harrowing sequence in which Billy falls from the monkey bars at the playground, Justin had to lie on the pavement and cry through fake blood. Knowing how the crew had befriended Justin, Dustin crouched over and explained that film families are temporary and he would probably never see his pals again.

“You know Eddie?,” Dustin said, pointing to a crew guy. “You may not see him.”

Justin burst into tears. Even after the scene was done, he couldn’t stop sobbing.

With his adult co-stars, Dustin’s tactics had more mixed success. Gail Strickland, the actress hired to play Ted’s neighbor Margaret, was so rattled by the intensity of their scenes that she developed a nervous stammer within the first few days. When it became clear that most of her dialogue would be unusable, she was replaced by Jane Alexander. (According to Strickland, everything was going fine until Dustin asked her to memorize a new batch of improvised lines. When she couldn’t do it fast enough he got “agitated,” and she was fired two days later.) Alexander had acted with Dustin in All the President’s Men and enjoyed his “febrile” way of working. She was taken aback, though, when she told Dustin she didn’t care to watch the dailies and he responded, “You’re a fucking fool if you don’t.”

Then there was Meryl. Unlike Strickland, she hadn’t buckled under the pressure of Dustin’s aggressive technique. When asked, she’d say she regarded him like one of her kid brothers, always seeing how far he could push. “I never saw one moment of emotion leak out of her except in performance,” Benton said. She thought of the movie as work, not as a psychological minefield.

As they sat in J.G. Melon, she had a question. The way the restaurant scene was written, Joanna starts off by telling Ted that she wants custody of Billy. Then, as Ted berates her, she explains that all her life she’s felt like “somebody’s wife or somebody’s mother or somebody’s daughter.” Only now, after going to California and finding a therapist and a job, does she have the wherewithal to take care of her son.

Wouldn’t it be better, Meryl asked on set, if Joanna made the “somebody’s wife” speech before revealing her intention to take Billy? That way, Joanna could present her quest for selfhood as a legitimate pursuit, at least as the character saw it. She could say it calmly, not in a defensive crouch. Benton agreed that re-structuring the scene gave it more of a dramatic build.

But Dustin was pissed. “Meryl, why don’t you stop carrying the flag for feminism and just act the scene,” he said. Just like Joanna, she was butting in and mucking everything up, he felt. Reality and fiction had become blurry. When Dustin looked across the table, he saw not just an actress making a scene suggestion but shades of Anne Byrne, his soon-to-be ex-wife. In Joanna Kramer, and by extension Meryl Streep, he saw the woman making his life hell.

In any case, Dustin had a scene suggestion of his own, one he kept secret from Meryl. Between takes, he approached the cameraman and leaned in. “See that glass there on the table?” he said, nodding toward his white wine. “If I whack that before I leave”—he promised to be careful—“have you got it in the shot?”

“Just move it a little bit to the left,” the guy said out of the corner of his mouth.

In the next take, Dustin smacked the wineglass and it shattered on the restaurant wall. Meryl jumped in her chair, authentically startled. “Next time you do that, I’d appreciate you letting me know,” she said.

There were shards of glass in her hair. The camera caught the whole thing.

Courtroom Drama

She showed up at the appointed time at the Tweed Courthouse, the massive stone edifice at 52 Chambers Street. “We were all wrecked and tired,” Benton recalled. Dustin was getting sick. Everyone else was sick of Dustin. And the courtroom scene would be particularly onerous. For every shot of a witness giving testimony, Benton would need three or four reaction shots: Ted, Joanna, the judge, the opposing counsel. The whole thing would take several days.

First on the stand: Joanna Kramer. Benton had been struggling with her testimony, which he saw as absolutely crucial. It is the one chance she has to make her case—not just for custody of Billy but for her personal dignity and, by extension, womankind. For most of the movie, she has been a phantom, with phantom motives. Then her lawyer asks, “Mrs. Kramer, can you tell the court why you are asking for custody?”

Benton had written his own version of her reply, a spin on Shylock’s “If you prick us, do we not bleed?” speech in The Merchant of Venice: “Just because I’m a woman, don’t I have a right to the same hopes and dreams as a man? Don’t I have a right to a life of my own? Is that so awful? Is my pain any less just because I’m a woman? Are my feelings any cheaper?”

Benton wasn’t happy with it. At the end of the second day of shooting—right after Dustin slapped her and goaded her in the elevator—the director had taken Meryl aside. “There’s a speech you give in the courtroom,” he told her, “but I don’t think it’s a woman’s speech. I think it’s a man trying to write a woman’s speech.” Would she take a crack at it? Meryl said yes. Then Benton walked home and promptly forgot he’d asked her.

Now, several weeks and many frayed nerves later, Meryl was handing the director a legal pad with her handwriting scrawled on it and telling him brightly, “I have the speech you told me to write.” She had written it on the way back from Indiana, where she had been visiting Don Gummer’s parents. The couple had married on September 30, an Indian-summer day, at her parents’ home on Mason’s Island, Connecticut.

Oh, why did I do that?, Benton thought. He had no time for this. Now he’d have to overrule her. I’m going to lose a friend. I’m going to lose a day of shooting. I’m going to maybe destroy a performance.

Then he read the speech, and exhaled. It was wonderful—though about a quarter too long. Working fast, he and Meryl crossed out a few redundant lines, then had it typed up.

She took the stand in a tan blazer and a matching skirt, her hair flung over her left shoulder. As the cameras rolled, Meryl spoke the words she had written herself:

JOANNA: Because he’s my child. And because I love him. I know I left my son, I know that that’s a terrible thing to do. Believe me, I have to live with that every day of my life. But in order to leave him, I had to believe that it was the only thing I could do. And that it was the best thing for him. I was incapable of functioning in that home, and I didn’t know what the alternative was going to be. So I thought it was not best that I take him with me. However, I’ve since gotten some help, and I have worked very, very hard to become a whole human being. And I don’t think I should be punished for that. And I don’t think my little boy should be punished. Billy’s only seven years old. He needs me. I’m not saying he doesn’t need his father. But I really believe he needs me more. I was his mommy for five and a half years. And Ted took over that role for eighteen months. But I don’t know how anybody can possibly believe that I have less of a stake in mothering that little boy than Mr. Kramer does. I’m his mother.

Tearily, she repeated, “I’m his mother.” But the word that slayed Benton was “mommy.” “I could have never imagined writing that,” he said. No longer the aloof tennis addict of Corman’s novel, Joanna now had a vivid inner life, full of yearning and tenderness and regret.

Benton filmed the speech in a wide shot first, reminding Meryl to save her energy for the close-up. But she delivered it with “the same sense of richness” each time, even when the cameras turned on Dustin for his reaction. “Part of the pleasure she must have taken is showing to Dustin she didn’t need to be slapped,” the director said. “She could have delivered anything to anybody at any time.”

They wrapped for the day. When they returned to the Tweed Courthouse, it was to shoot one of the most wrenching scenes in the film: Joanna’s cross-examination by Ted’s lawyer, John Shaunessy, played with cowboy-like bluster by Howard Duff. Benton had taken this sequence nearly word for word from the book, and its purpose was clear: to dismantle Joanna’s tenuous self-esteem in a way that even Ted finds heartless.

Right away, Shaunessy badgers Joanna with questions: Did Mr. Kramer ever strike you? Was he unfaithful? Did he drink? How many lovers have you had? Do you have one now? As Joanna begins to falter, he goes in for the kill. Hunching over her on his cane, he asks her to name the “longest personal relationship” of her life. Wasn’t it with her ex-husband?

“Yes,” she murmurs.

So, hadn’t she failed at the most important relationship in her life? “It did not succeed,” she answers weakly.

“Not it, Mrs. Kramer,” he bellows, sticking an accusatory finger in her face. “You. Were you a failure at the one most important relationship in your life? Were you?” It’s at that moment we see the “whole human being” Joanna believes herself to be crumble before our eyes, trapped like a sea creature in a fisherman’s net.

Before the take, Dustin had gone over to the witness stand to talk to Meryl. He needed her to implode on-camera, and he knew the magic words to make it happen: “John Cazale.” Out of Benton’s earshot, he started whispering the name in her ear, planting the seeds of anguish, as he had in the elevator scene. He knew she wasn’t over the loss. That’s why she’d gotten the part. Wasn’t it?

Now, with a fat finger waving three inches from her face, Meryl heard the words “Were you a failure at the one most important relationship in your life?” Her eyes watered. Her lips tensed. Dustin had instructed her to look at him when she heard that line. When she did, he gave a little shake of his head, as if to say, “No, Meryl, you weren’t a failure.”

Who exactly was up on the stand? Was it the actress who had stormed into the hotel room, guns blazing, telling three powerful men to re-write their screenplay? Wasn’t that who she had always been: self-assured, proficient at everything? Or was Dustin right? Was she “barely there,” just like Joanna Kramer?

As she sat on the witness stand, defending her life, was she thinking about John? Or was she acting despite Dustin’s meddling? By her own admission, the grief was still with her. “I didn’t get over it,” she told Ladies’ Home Journal two years later. “I don’t want to get over it. No matter what you do, the pain is always there in some recess of your mind, and it affects everything that happens afterwards. John’s death is still very much with me. But, just as a child does, I think you can assimilate the pain and go on without making an obsession of it.”

When Benton saw Meryl glance to the side, he noticed Dustin shaking his head. “What was that? What was that?” the director said, bounding over to Dustin. Unwittingly, Dustin had created a new moment, one that Benton wanted in the scene. He turned the cameras around and had Meryl act the cross-examination again, and this time he recorded Dustin’s reactions. Now the head shake meant something else. It was Ted Kramer telling Joanna Kramer, “No, you didn’t fail as a wife. You didn’t fail as a mother.” Amid the rancor of the court proceeding, it was a final gesture of the love they once had.

They filmed the remaining testimonies, and the court sequence was in the can. At one point between takes, Dustin went up to the actual court reporter they’d hired to sit behind the stenograph machine.

“Is this what you do?” he asked. “Divorces?”

“Oh, I did them for years,” the woman said, “but I burned out. I couldn’t do it anymore. It was just too painful.” She added cheerfully, “I really love what I’m doing now.”

“What?” Dustin asked.

“Homicides.”

Scene and Heard

Benton knew there was something wrong with the ending of Kramer vs. Kramer virtually the moment he shot it. He had toyed with the idea of closing the movie on a re-united Ted and Billy walking through Central Park. The camera pulls out to reveal that they’re just two out of thousands of parents and children enjoying a sunny afternoon in New York City.

But he realized early on that there were two stories embedded in the movie. One is Ted’s relationship with Billy, which is resolved somewhere around the playground-accident scene, when Ted realizes that nothing in the world comes before his love for his son. The second story is about Ted and Joanna: after the brutality of the custody hearing, how can they ever be functioning co-parents?

That’s the conflict Benton needed to resolve in the final scene, which he set in the lobby of Ted’s building. It’s the day Joanna comes to take Billy, some time after she has won the custody battle. She buzzes up and asks Ted to come downstairs, where he finds her leaning against the wall in her trench coat. She tells him she isn’t taking Billy after all.

JOANNA: After I left … when I was in California, I began to think, what kind of mother was I that I could walk out on my own child. It got to where I couldn’t tell anybody about Billy—I couldn’t stand that look in their faces when I said he wasn’t living with me. Finally it seemed like the most important thing in the world to come back here and prove to Billy and to me and to the world how much I loved him … And I did … And I won. Only … it was just another “should.”

Then Joanna asks if she can go upstairs and talk to Billy, and both parents get in the elevator. The picture ends with the doors closing on the Kramers, united as parents, if not as spouses.

They shot the scene in late 1978, in the lobby of a Manhattan apartment building. But as Benton pieced the film together, the ending didn’t sit right. One problem was Joanna’s reasoning. If she had really come back because of how people looked at her in California, that meant she was the same deluded narcissist of Corman’s novel, not the ambivalent, vulnerable woman Meryl was playing. It was too much about her: her pride, her guilt, her endless search for self-actualization.

The second problem was the final shot in the elevator. It looked too much like Ted and Joanna were getting back together. This couldn’t be a Hollywood ending, with the audience imagining the final kiss behind the elevator door. Benton wanted to leave no doubt: even if the Kramers were moving forward as parents, their marriage was definitively over.

Early in 1979, the director called back Dustin and Meryl for re-shoots. The lobby where Benton had filmed the first ending was unavailable, so the crew built a replica. It had been the cinematographer Néstor Almendros’s idea to paint Billy’s room with clouds around his bed. They would symbolize the cocoon of home and act as a reminder, like Justin Henry’s flaxen hair, of the missing mother. In the re-written ending, the clouds were the catalyst for Joanna’s change of heart.

JOANNA: I woke up this morning … kept thinking about Billy. And I was thinking about him waking up in his room with his little clouds all around that I painted. And I thought I should have painted clouds downtown, because … then he would think that he was waking up at home. I came here to take my son home. And I realized he already is home.

Meryl delivered the speech with trembling certainty, inserting a fortifying gasp between “painted” and “clouds.” It was Joanna, as Benton saw it, who now performed the film’s ultimate heroic act: sacrificing custody not despite her love for Billy but because of it.

This time, Joanna got in the elevator alone. In the final moments, she wipes her tears away and asks Ted how she looks. “Terrific,” he says as the door closes between them. Her wordless, split-second reaction was as richly textured as Dustin’s stare at the end of The Graduate—both flattered and disbelieving, the face of someone who’s been given just the right gift at just the right moment, by the most unlikely person. What does the future hold for this woman, dangling between fragility and conviction?

“This picture started out belonging to Ted Kramer, and by the end it belonged to both of them,” Benton recalled. “And there was no way Dustin could shake her. No way he could do anything to shake her. She was just there, and she was an incredible force.” When she told Dustin she planned on going back to the theater, he said, “You’re never going back.”

Something else had changed between the first ending and the second: this time, Meryl was pregnant. Not enough to show, but enough that Joanna’s choice—a harbinger of Sophie’s—suddenly seemed unconscionable. She told Benton, “I could never have done this role now.”

Opening Night

The film opened on December 19, 1979. As the producers had hoped, it was received less as a movie than as a cultural benchmark, a snapshot of the fractured American family, circa now. Vincent Canby, in The New York Times, wrote, “ ‘Kramer vs. Kramer’ is a Manhattan movie, yet it seems to speak for an entire generation of middle-class Americans who came to maturity in the late 60’s and early 70’s, sophisticated in superficial ways but still expecting the fulfillment of promises made in the more pious Eisenhower era.”

Indeed, the public greeted the film with open wallets. On its opening weekend, it played in 524 theaters, grossing more than $5.5 million. In the filmmaking world that Star Wars had wrought, a chamber drama about a failed marriage was no longer Hollywood’s idea of big money. But the U.S. gross of Kramer vs. Kramer would total more than $106 million, making it the biggest domestic moneymaker of 1979—beating out even Star Wars progeny such as Star Trek and Alien, starring Meryl’s former Yale classmate Sigourney Weaver.

It was a movie people wept over and argued over, a well-made tearjerker about a father and son. Anyone who was or ever had a loving parent could relate to that story. But there was a trickier story lurking within—the shadow narrative of Joanna Kramer. In celebrating the bond between Ted and Billy, had the movie sold out not only her but the feminist movement? Some people seemed to think so. The Washington Post’s Gary Arnold found it “difficult to escape the conclusion that Dear Mrs. Kramer is a dim-witted victim of some of the sorriest cultural cant lately in vogue.”

Leaving the theater with her 15-year-old daughter, the writer Barbara Grizzuti Harrison felt a trifle manipulated. Why do we applaud the noble self-sacrifice of Ted Kramer, she wondered, when the same thing is merely expected of women? How does Joanna land a re-entry job for $31,000 a year? Why don’t we ever see Ted arranging for a babysitter? And what to make of Joanna’s hazy quest for fulfillment? “I keep thinking of Joanna,” Harrison wrote in Ms. magazine, the standard-bearer of mainstream feminism. “Is she outside howling at the gates of happiness, or is she satisfied with her job, her lover, and occasional visits to Billy. Who is Joanna, and did she spend those 18 months in California in vain?”

In February, Kramer vs. Kramer was nominated for nine Academy Awards, including best picture (Stanley Jaffe, producer), best actor (Hoffman), best director (Benton), and best adapted screenplay (Benton again). Eight-year-old Justin Henry, nominated for best supporting actor, became the youngest Oscar nominee in history. And Meryl, along with Barbara Barrie (Breaking Away) and Candice Bergen (Starting Over), would compete for best supporting actress against two of her co-stars: Jane Alexander from Kramer vs. Kramer and Mariel Hemingway from Woody Allen’s Manhattan.

April 14, 1980. Outside the Dorothy Chandler Pavilion, the stars of the new decade arrived in style: Goldie Hawn, Richard Gere, Liza Minnelli, George Hamilton. Among the movie gods was Meryl Streep, one of the only women not in sequins.

Inside, she took her seat between her husband and Sally Field, nominated for best actress for Norma Rae. Meryl sat nervously through Johnny Carson’s monologue, with zingers covering The Muppet Movie, Bo Derek’s cornrows in 10, Anwar Sadat, Dolly Parton’s chest (“Mammary vs. Mammary”), and the fact that three of the big films that year were about divorce. “It says something about our times when the only lasting relationship was the one in La Cage aux Folles,” Carson observed. “Who says they’re not writing good feminine roles anymore?”

Jack Lemmon and Cloris Leachman came out to deliver the first award of the night: best supporting actress. When she heard her name, last among the nominees, Meryl rubbed her hands together and mumbled something to herself. “And the winner is … ,” Leachman said, before handing the envelope to Lemmon.

“Thank you, my dear.”

“You’re welcome, my dear.”

“Meryl Streep in Kramer vs. Kramer.”

The hall reverberated with Vivaldi’s Mandolin Concerto in C Major, the movie’s theme. As she hurried to the stage, she leaned over and kissed Dustin on the cheek. Then she glided up the stairs to the microphone and took hold of her first Academy Award.

“Holy mackerel,” she began, glancing down at the statuette. Her tone was placid. “I’d like to thank Dustin Hoffman and Robert Benton, to whom I owe … this. Stanley Jaffe, for giving me the chance to play Joanna. And Jane Alexander, and Justin”—she blew a kiss—“for the love and support during this very, very delightful experience.”

After one last “thank you very much,” she held up the Oscar and headed left, before Jack Lemmon was kind enough to point her right.

Vivaldi played again for best adapted screenplay, best director, and best actor. Dustin Hoffman, accepting his Oscar from Jane Fonda, reiterated his well-known contempt for award shows (“I’ve been critical of the Academy, and for reason”). Justin Henry lost to Melvyn Douglas (Being There), 71 years his senior, becoming so distraught that Christopher Reeve, one of the only movie stars he recognized, had to be called over to console him. At the end of the night, Charlton Heston announced the winner for best picture: it was a Kramer vs. Kramer sweep.

In the moments after the ceremony, the Kramer vs. Kramer winners were shown into a room of about a hundred reporters. “Well, the soap opera won,” Dustin boomed as he walked in, anticipating their disdain. It was clear that this wouldn’t be a typical glad-handing press conference, and the reporters were eager to match Dustin’s feistiness. The columnist Rona Barrett remarked that many women, particularly feminists, “feel this picture was a slap to them.”

“That wasn’t said at all,” Dustin snapped back. “I can’t stop people from feeling what they are feeling, but I don’t think everyone feels that way.”

As they argued, Meryl bounded onto the platform. “Here comes a feminist,” she said. “I don’t feel that’s true at all.” Having commandeered the stage, she continued: “I feel that the basis of feminism is something that has to do with liberating men and women from prescribed roles.”

She could have said the same about acting—or at least her version of it, the kind she had fought so hard to achieve. She was no longer the college freshman who thought that feminism had to do with “nice nails and clean hair,” as she later described herself. In fact, it was inseparable from her art, because both required radical acts of imagination. Like an actress stretching her versatility, Joanna Kramer had to imagine herself as someone other than a wife and a mother in order to become a “whole human being,” however flawed. That may not have been apparent to Avery Corman, but it was to Meryl, and tonight’s triumph seemed to underscore that she was right.

Someone asked her, “How does it feel?”

“Incomparable,” she said. “I’m trying to hear your questions above my heartbeat.” If she seemed composed, it was all an act. Earlier, as she had wandered backstage after her acceptance speech, she stopped in the ladies’ room to catch her breath. Her head was spinning. Her heart was pounding. After a moment of solitude, she headed back out the door, ready to face the big Hollywood hoopla. “Hey,” she heard a woman yell, “someone left an Oscar in here!” Somehow, in her tizzy, she had left the statuette on the bathroom floor.

Adapted from Her Again: Becoming Meryl Streep, by Michael Schulman, to be published in April by Harper, an imprint of HarperCollins Publishers; © 2016 by the author.