Joaquin Phoenix, Hilary Swank, Shia LaBeouf take acting to extremes with slaps, diets and pulled teeth

Joaquin Phoenix and Vanessa Kirby took commitment to their roles to the next level on the set of their upcoming movie "Napoleon."

The 48-year-old actor slapped the 35-year-old actress while they were shooting a heated scene after the two made an agreement to "shock each other" on the set of the upcoming historical drama. 

Phoenix and Kirby, who star as Napoleon Bonaparte and his wife Josephine de Beauharnais, told Empire magazine they talked ahead of filming and decided to give each other full creative freedom when improvising physical interactions.

"She said, ‘Look, whatever you feel, you can do.’ I said, ‘Same thing with you.’ She said, ‘You can slap me, you can grab me, you can pull me, you can kiss me, whatever it is,’" Phoenix recalled.

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The Oscar winner continued, "We had this agreement that we were going to surprise each other and try and create moments that weren’t there, because both of us wanted to avoid the cliché of the period drama."

While method acting has often resulted in rave reviews and prestigious awards, some actors occasionally take the technique to extremes – leading to offended co-stars, physical ailments and near-death experiences.

Here's a look at other actors who pushed method acting to the limit.

Dustin Hoffman and Meryl Streep

Meryl Streep and Dustin Hoffman played warring exes in the 1979 divorce drama "Kramer vs. Kramer." The movie became a hit and won the Academy Award for best picture, best director and best adapted screenplay, as well as best actor and best supporting actress for Hoffman and Streep.

However, rumors persisted for years that Hoffman slapped Streep, who was then an up-and-coming actress, ahead of an emotional scene to provoke a more genuine reaction from her. 

In the wake of the #MeToo movement in 2018, Streep addressed the speculation for the first time in an interview with the New York Times.

Upon being asked if Hoffman had slapped her, Streep replied, "This is tricky because when you're an actor, you're in a scene, you have to feel free. I'm sure that I have inadvertently hurt people in physical scenes. But there's a certain amount of forgiveness in that."

She continued, "But this was my first movie, and it was my first take in my first movie, and he just slapped me. And you see it in the movie. It was overstepping."

"But I think those things are being corrected in this moment," Streep added. "And they're not politically corrected; they're fixed. They will be fixed, because people won't accept it anymore. So that's a good thing."

At the time, Hoffman was going through a divorce of his own after separating from his first wife Anne Byrne. He later admitted that he was channeling his own feelings into his performance.

"It was the first time I ever made a movie where I was living through what I was acting – unlike a writer or painter, who gets up in the morning and can exorcise what they're going through," Hoffman said in the 2001 documentary "Finding The Truth: The Making of ‘Kramer vs. Kramer.'"

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He continued, "It's quite unusual to be getting a divorce, my first and only divorce, at the time I'm shooting a movie about a man getting a divorce."

"I'm sure I was acting out on her throughout the movie," Hoffman acknowledged, referring to Streep. "Stuff that I was feeling toward the wife that I was divorcing in real life."

At one point during filming, Hoffman hurled a wine glass at an unsuspecting Streep, who was left with shards in her hair.

"She was p-----," he recalled.

Emma Stone and Willem Dafoe

While Willem Dafoe doesn't describe himself as a method actor, he is known for thoroughly engrossing himself in his roles.

The four-times Academy Award nominee recently co-starred with Emma Stone in Yorgos Lanthimos' upcoming anthology film "And," after previously appearing in the director's science-fiction romance "Poor Things."

In one scene, Stone's character slaps Dafoe's character while he is off-screen, an action that she typically would have mimed without him present. However, the "Spiderman" actor insisted on remaining on set and having Stone actually slap him over 20 times to ensure that the scene looked realistic, according to the New York Times.

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Lanthimos praised Dafoe for his commitment, telling the outlet, "That’s what you want from actors… to want to be part of it in any way."

The "La La Land" star also complimented Dafoe's dedication to his craft. "There’s this instinct to perform that many actors have – the ‘Look at me, look at me!’ kind of performer," Stone said. "He’s the opposite of that. Maybe it’s changed through the years. A lot of actors I bond with have been doing this for a long time, and you know they’ve gone from ‘I’ to ‘We.’"

Shia LaBeouf 

Shia LaBeouf's commitment to embodying his character in the 2014 war film "Fury" was so drastic, it alarmed his co-stars, including Brad Pitt, Logan Lerman and Scott Eastwood.

The 37-year-old actor repeatedly cut his face, pulled out a tooth and didn't bathe for the entirety of the production.

In a 2014 interview with GQ, Lerman recalled how the "Transformers" star began slashing his face because he thought the stage makeup didn't appear authentic.

"We were in make-up and they were putting cuts on Shia and I said, 'Yeah, yeah, it looks good.' And Shia was like, 'No, it doesn't look real,'" Lerman said.

He continued, "Then he walks out into the hallway and says, 'Hey man, wanna see something fun? Check this out...' and he takes out a knife and cuts his face. And for the whole movie he kept opening these cuts on his face. That's all real."

The "Percy Jackson" actor also confirmed that LaBeouf had one of his teeth extracted for the role, telling the outlet, "I mean, he didn't do it himself, he did go to a dentist and asked them to pull his tooth out but yeah, what an odd request."

During production, LaBeouf, who played tank gunner Boyd Swan, also learned how to drive a tank.  

"He really spent every moment on that set," Lerman told GQ. "He's the guy operating the turret in every shot, even when you don't need to be in there as an actor. You know, you can have somebody else inside. But he was there, for every shot."

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Eastwood recounted a scene in which his character was chewing tobacco and spit it out on LaBeouf's tank. Though the action was in the script, LaBeouf was apparently unaware and became offended.

"[LaBeouf] got mad at me and it turned into a volatile moment that Brad Pitt ultimately got in the middle of," Eastwood, who is the son of Clint Eastwood, told Insider in 2014.

He continued, "You’ve got to put things in perspective. This is make-believe, it’s fun, and at times it’s serious and you’re doing emotional work and you give people space to do that in, but everything has to have its parameters."

Eastwood went on to say, "I never think your process as an actor should ever hinder how people are treated on set."

"It should always enhance the production, not take away and put people in a situation where it’s a s----- work environment or you’re rude or people have to be in an uncomfortable situation," he added.

During an appearance on the YouTube series "Hot Ones," LaBeouf didn't deny "shaving [his] tooth down to the gum line" or not showering. The actor explained that his actions were "not to remain in character but to sort of rally the troops."

LaBeouf continued, "Just to sort of get everybody psyched. Rise and tide lifts all ships, so I would do something and [Jon] Bernthal would do something, and [Michael] Pena would do something... and we would all just try to get everybody involved."

Hilary Swank 

Hilary Swank won her second best actress Oscar for her performance in "Million Dollar Baby" but it almost cost the actress her life.

In order to portray boxer Maggie Fitzgerald in the 2004 film, Swank had to transform her body in just 90 days. 

"My training was two and a half hours of boxing and approximately an hour and a half to two hours lifting weights every day, six days a week," Swank told MovieWeb in 2005. "The producers asked me to gain 10 pounds of muscle. I gained 19 pounds of muscle." 

She continued, "I started at 110 and went to 129. And in order to do that, I had to eat 210 grams of protein a day. Now, your body can only assimilate so much protein, so I had to eat every hour and a half." 

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However, Swank revealed in an interview on "60 Minutes" that her extreme training led to a life-threatening staph infection.

"I was about halfway through my training when I got a blister… the size of my palm on the ball of my foot. And it was my front foot, the one I have to pivot on.... So, I popped it.… I popped it myself. I didn't let it pop on its own, whatever. I popped it on its own. And I did it in the bathtub," she recalled.

Over the next 48 hours, the blister became infected with staph bacteria. "I couldn't believe the pain," she says. "It was unbelievable. And I looked down… there were streaks going up my foot. So, I went to the doctor that second. And he looked at me, and he said, 'This is really serious. And if you would have waited two more hours, you would have been in the hospital for three weeks.' And if it gets to your heart, that's it."

Swank admitted that she kept the health scare a secret from her co-star Clint Eastwood and the film's producers and returned to the set after a few days of medicated rest.

"I didn’t tell Clint," she said. "The producers don’t know... because in the end, that’s what happens to boxers: They get blisters, they get infected. They have injuries, and they keep pushing through it."

Jared Leto

Jared Leto is famous for fully immersing himself in his roles, but he took it to the next level when he played the Joker in the 2016 superhero movie "Suicide Squad."

In order to play the deranged villain, Leto's acting process involved sending strange gifts to his co-stars, including Margot Robbie and Will Smith.

"He sent [Margot Robbie] a nice love letter with a black box with a rat in it – a live rat," Adam Beach, who played Slipknot, told E! News in 2016. "It was beautiful. Then he sent bullets to Will [Smith] with a letter."

Beach went on to say that Leto sent the cast a video of himself in character as the Joker as well as a "dead hog."

"Basically, what he said was, 'Guys, I can't be there, but I want you to know I'm doing my work as hard as you guys,'" Beach recalled. "The video he showed is in character. It blew our minds away. Then we realized that day, this is real."

Viola Davis, who played Suicide Squad director Amanda Waller, recalled Robbie's surprising reaction to Leto's unusual present in an interview with British Vogue.

"I was saying loudly, ‘Don’t open the box!’ I was halfway out the door when [Robbie] opened the box," Davis remembered. "And saw the biggest black rat you could imagine. Then… she cooed at it. No fear. Open. Receptive. Full of joy."

During an appearance on "The Tonight Show Starring Jimmy Fallon," Robbie recounted the incident.

"At first I thought this was disgusting. But then after that… I was like, I’m not going to kill him," the "Barbie" star said. "So I ended up keeping him as a pet."

She continued, "I ended up getting him like a sweet little playpen, a slide, a hammock, and a leash because I wanted to take him to set and walk him around. But then our landlord at the place I was staying found out."

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Smith later revealed that the "Haunted Mansion" actor stayed in character throughout the entire production.

"I’ve never actually met Jared Leto," Smith explained in a Beats 1 interview, via Complex. "We worked together for six months and we’ve never exchanged a word outside of ‘Action!’ and ‘Cut!’" 

"I literally have not met him yet," Smith added. "So, the first time I see him will be ‘Hey, Jared. What’s up?’ He was all in on the Joker."

Natalie Portman

Natalie Portman won her first Academy Award for her portrayal of troubled ballerina Nina in the 2010 psychological horror film "Black Swan" but the achievement was not without consequences.

Though the actress had studied ballet during childhood, she required extensive additional training to accurately portray her character. Portman began preparing for the role a year in advance, training with a ballet coach from the New York City Ballet.

"We would do two hours a day for the first six months, and that was really just strengthening and getting me ready to do more, so that I wouldn’t get injured," she told Collider. 

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She continued, "And then, at about six months, we started doing five hours a day. We added in swimming, so I was swimming a mile a day, toning and then doing three hours of ballet class a day. And then, two months before, we added the choreography, so we were doing probably eight hours a day." 

"The physical discipline of it really helped for the emotional side of the character because you get the sense of the monastic lifestyle of only working out, that is a ballet dancer’s life," Portman added. "You don’t drink, you don’t go out with your friends, you don’t have much food and you are constantly putting your body through extreme pain, so you get that understanding of the self-flagellation of a ballet dancer."

Toward the end of her training, Portman told NPR that she was also swimming miles and cross-training. Subsisting on a diet of carrots and almonds, she lost about 20 pounds during that time.

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However, the "Thor" star told the outlet that her "body paid a price." She recalled that she got callouses on her feet, her toenails fell off, and she suffered a dislocated rib after a lift.

"But it wasn't the end of the world," Portman said. "Real dancers dance with such incredible injuries that you wouldn't even believe."

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She continued, "It's a nightmare for them to be replaced once they've made it to the top and they get these roles. [So] they will dance with a sprained ankle or torn plantar fascia or twisted necks just to make sure they can keep their moment."

However, Portman revealed to Entertainment Weekly that sometimes she felt that the grueling process would kill her.

"There were some nights that I thought I literally was going to die," Portman recalled. "It was the first time I understood how you could get so wrapped up in a role that it could sort of take you down."