Dustin Hoffman reportedly slapped and taunted Meryl Streep on the 'Kramer vs. Kramer' set

In the cover story for Vanity Fair's April issue, readers get an inside look at the making of the Oscar-winning 1979 drama "Kramer vs. Kramer," and it doesn't hold back on the on-set drama.

Publishing an excerpt from his upcoming biography, "Her Again: Becoming Meryl Streep," author Michael Schulman writes about Streep's grieving as she went into the film. The then-27-year-old had just lost her 41-year-old boyfriend, actor John Cazale, to lung cancer.

The movie would nab five Oscars, including Streep's first Oscar win and best actor for costar Dustin Hoffman, but according to Schulman's book, Hoffman did horrific things to Streep to get the performance he felt she needed to deliver.

Enabled by the film's director, Robert Benton, according to the Vanity Fair story, Hoffman actually wanted to draw on Streep's loss of Cazale, best known for playing Fredo Corleone in "The Godfather," months before she auditioned for "Kramer vs. Kramer." The actor and director saw "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," Schulman writes.

The film follows the bitter custody battle over divorced couple Ted (Hoffman) and Joanna's (Streep) son.

To get the emotion he wanted out of Streep, Hoffman allegedly slapped Streep on the set and would bring up Cazale to her.

According to Schulman:

"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."

But Hoffman was just getting started:

"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,' [film executive Richard] 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.'"

Streep stormed off the set in a rage. But Hoffman's tactics didn't end.

In another scene, Hoffman had an idea that he didn't reveal to Streep. He asked a cameraman about a wine glass, "If I whack that before I leave, have you got it in the shot?" Eventually during filming, he indeed shattered the wine glass against the wall without warning, leaving shards of glass in Streep's hair.

During the divorce hearing scene in which Joanna has an emotional outburst on the stand, according to the Vanity Fair story, Hoffman knew what would set her off: saying John Cazale's name.

"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," Schulman reports.

To Streep's credit, she seems to have taken all the insane Method tactics Hoffman threw at her. And finally showed Hoffman, and the whole crew, she could shine on her own. In one of the final scenes shot for the divorce hearing, she came to Benton with a speech she wrote that Joanna would deliver on the stand during the hearing.

Here's the speech Streep wrote.

"Part of the pleasure she must have taken is showing to Dustin she didn't need to be slapped," the director says in the story. "She could have delivered anything to anybody at any time."

A spokeswoman for Streep said regarding the Vanity Fair story: "Ms Streep has no comment on this book. It was unauthorized. She made no contribution to it, nor has she read it."

Dustin Hoffman's representative was not immediately available for comment to Business Insider.