Many actors take their roles seriously to the point where no one knows who the real person behind the role is. Richard Gere is an example of an actor who went above and beyond. In Time Out Of Mind, he wanted to raise awareness for the homeless by working with the Coalition for Homeless and spoke directly with homeless New Yorkers.

Some actors sacrificed more than they should have. From strict diets to unrecognizable costumes and makeup, to taking it so far as putting their lives on the line, some actors are serious about their work. Their drastic changes were either rewarding, or it was a role they should have never taken on.

$20,000 Of Dentures For Robert De Niro

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The remake of Cape Fear brought out Robert De Niro's crazy side. An example of the extremes he was willing to go through was when De Niro paid a dentist $20,000 to grind and stain his teeth. The role won De Niro Oscar an Golden Globe nomination, giving him a wide range of recognition.

Piercings All Over The Place For Rooney Mara

Photo Credit: Scott Rudin Productions/MovieStillsDB

Rooney Mara pierced her face and nipples for The Girl With The Dragon Tattoo. She wanted to meet fans' expectations so Mara bleached her eyebrows, chopped off her hair, and learned martial arts. The actress wandered around Stockholm by herself to feel character Lisbeth's sense of isolation.

Billy Bob Thornton Walked On Broken Glass

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Billy Bob Thornton felt like he had a lot to prove in his directorial debut Sling Blade. Outside of his appearance which no one could recognize, Thornton added broken pieces of glass to the bottom of his shoes. That gave to a whole new meaning behind the word "cut" on set, and it helped earn Thornton an Oscar.

Jamie Foxx went on a strict diet that landed him an Oscar.

Samuel L. Jackson Called The Shots On His Hairdo

Photo Credit: Miramax Films/MovieStillsDB

Samuel L. Jackson's portrayal of the Bible-quoting hit-man Jules Winnfield would have had a different appearance if the actor hadn't stepped in. Jackson's Jheri curls were by accident. Pulp Fiction director Quentin Tarantino wanted Jackson to wear a huge afro wig. Of course, that never happened when they shot the film.

Shia LaBeouf Cut Up His Face

Photo Credit: Columbia Pictures/MovieStillsDB

Shia LaBeouf had a strong commitment when he shot Fury. The Transformers star cut up his face and went on to pull out a tooth while avoiding bathing for months. He joined the U.S. National Guard, got baptized, and became a chaplain's assistant to Captain Yates for the 41st Infantry in his role.

Jamie Foxx Fasted For A Full Week And Lost 30 Pounds

Photo Credit: Universal Pictures/MovieStillsDB

Jamie Foxx followed a strict diet and daily workouts to lose 30 pounds. Foxx even agreed to wear prosthetic eyelids glued over his eyes to mimic Ray Charles' blindness. Foxx also learned to play all of the piano parts in the film, helping cement his Oscar win for Best Actor.

Charlize Theron's most unrecognizable moment was in a 2003 biographical crime drama.

Christian Bale Is Unrecognizable After Losing Weight

Photo Credit: Paramount Classics/MovieStillsDB

It's hard to believe that Christian Bale lost over 60 pounds for his role in The Machinist. The British actor dropped another 20 pounds even after his nutritionist said he was good to shoot. He survived by eating an apple a day and a can of tuna fish.

Margot Robbie Can Hold Her Breath Underwater For Five Minutes

Photo Credit: Warner Bros./MovieStillsDB

Margot Robbie has established a name for herself thanks to playing Harley Quinn. The Aussie actress learned how to hold her breath underwater for five minutes for a fight scene in Suicide Squad. Robbie was competitive with her stunt double, so she wanted to prove her mad skills.

Charlize Theron, Is That You?

Photo Credit: Denver & Delilah Films/MovieStillsDB

Charlize Theron went unrecognizable as Aileen Wuornos in Monster. Her makeup teams transformed her skin and hair to mirror Wuornos' real-life appearance. In a role like that, Theron felt she couldn't have done the film without drastically changing her looks.

One actor ate raw buffalo meat to get prepared for his role.

Halle Berry Went A Week Without A Shower

Photo Credit: 40 Acres And A Mule Filmworks/MovieStillsDB

For Halle Berry's first film, Spike Lee felt she wasn't the type to play a prostitute. So Berry went to visit an actual crack den to prepare to play the role of Vivian. Berry didn't bother to shower for over a week as she was only on set for ten days to shoot her parts.

Natalie Portman Got Fit Like A Ballet Dancer

Photo Credit: Twentieth Century Fox/MovieStillsDB

Portman did her homework when she trained with Mary Helen Bowers, a former New York City ballet dancer, for over a year while shooting Black Swan. The actress supplemented dance class with swimming and endurance exercises. Portman wanted to perform Benjamin Millepied's tricky choreography too.

Raw Buffalo Meat Was Leo's Go-To Meal

Photo Credit: Twentieth Century Fox/MovieStillsDB

Leonardo DiCaprio found the role that finally won him an Oscar. Before that particular moment happened, the actor slept in a horse carcass while eating raw buffalo meat during the nine-month shoot. DiCaprio wanted to be as truthful as he could be for the experience, and tossing himself in and out of freezing rivers helped too.

It's no surprise that Daniel Day-Lewis uses irregular methods to prepare for a role.

Jim Carey's Method Actor Strategy Was Too Much

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Playing the role of your idol can be daunting. For Jim Carrey, he walked around on the set of Man On The Moon as the late Andy Kauffman. Carrey would have people on set call him "Andy" while staying in character through the whole film. That didn't help when Carrey annoyed Jerry Lawler, who had a real-life feud with Kauffman.

Heath Ledger Lived In A Hotel By Himself

Photo Credit: Warner Bros./MovieStillsDB

The Joker wasn't a character Heath Ledger could quickly get into. Ledger reached out to Jack Nicholson, but not long before the late actor locked himself in a hotel room for a month. With no outside contact, Ledger wrote in a personal diary where he wrote some deep and dark content.

Daniel Day-Lewis Spent A Summer At Hog Island

Photo Credit: Twentieth Century Fox/MovieStillsDB

Daniel Day-Lewis has some irregular ways of preparing for a role. In The Crucible, Lewis spent a summer at Hog Island before filming began. He rode to work on a brown horse while living without running water or electricity for the duration of the film.

One actress went as far as speaking in a low voice and introducing herself as "Hilary's brother James."

Jared Leto Left His Co-Stars A Dead Pig

Photo Credit: Warner Bros./MovieStillsDB

Jared Leto was absurd on the set of Suicide Squad. Not only did he stay in character, but he also sent the rest of the cast a dead pig. The strange gift to his castmates was a reminder that Leto was taking the role of the Joker very seriously, but the box office said differently.

Anne Hathaway Followed A Near-Starvation Diet

Photo Credit: Universal Pictures/MovieStillsDB

Realism caught up to Anne Hathaway when she dropped 25 pounds thanks to eating two thin squares of dried oatmeal paste. The commitment from the Les Misérables star went further when she shaved her head. Nevertheless, Hathaway won a best-supporting-actress Oscar.

Hilary Swank Went Into All Boy Mode

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Months before Boys Don't Cry began filming, Hilary Swank went out in public dressed as a male. She went so far as to speak in a low voice and introduce herself as "Hilary's brother James." Swank dramatic experiment ultimately led her to an Oscar for the role.

Adrian Brody Gave Up A lot To Move To Europe

Photo Credit: Focus Features/MovieStillsDB

The actor gave up his apartment and his car while moving to Europe, with only two bags. Brody wanted to feel Wladyslaw Szpilman's discomfort, and he went on a crash diet where he lost 30 pounds in six weeks. Lessons on the piano and a thinner body won Brody his only Oscar.

50 Cent Can Act

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The New York rapper dropped a little over 50 pounds in All Things Fall Apart. He went on a liquid diet while spending three hours a day on a treadmill. Some fans couldn't even recognize 50 Cent when photo stills of the aspiring actor were released.

Val Kilmer Lived Like Jim Morrison

Photo Credits: Tri-Star Pictures

In order to prepare for the role of Jim Morrison in The Doors, actor Val Kilmer lived like Jim Morrison for a whole year before shooting began. During that time, he wore the same clothes as Morrison, listened to the same music, read the same books, and even frequented some of Morrison's favorite bars.

Bruno Ganz Wanted To Show A Different Side Of Hitler

Photo Credits: Constantin Film

While when most actors portray Hitler, they tend to try and show the loud and violent side of the man. For the film Downfall,actor Bruno Ganz decided that he wanted to try and show the more quiet side to Adolf Hitler. In order to do this, he poured over hours of conversations that were recorded of Hitler in order to be able to imitate it personally.

People Were Worried About Matthew McConaughey

Photo Credits: Focus Features

Matthew McConaughey dropped a reported 40 pounds for his portrayal of Ron Woodruff in 2013’s Dallas Buyer’s Club. In order to achieve his gaunt look, he simply just stopped eating. No workout routines or anything, just very little food. He told Vanity Fair that people kept asking him if he was okay or suggesting he seek help and he said, “There we go. That’s the perfect spot.”

Rene Zellweger Was Scared For Her Health

Photo Credits: Universal Pictures

Actress Renee Zellweger received a lot of harsh criticism for her weight in her role as Bridget Jones. Zellweger put on on a whopping 30 pounds for all three of the films in the trilogy. She commented that "I had a panic attack with all the specialists talking about how bad this is for you long-term, putting on that much weight in short periods of time."

Dallas Buyer's Club Was Hard On Numerous Actors

Photo Credits: Focus Features

Leto starred alongside Matthew McConaughey in Dallas Buyer’s Club as a transgendered woman named Rayon. In order to play the HIV-stricken character, he Leto dropped a reported 30 pounds by not eating. While filming, he refused to break character and said “After I while I stopped counting (the weight loss). It changes the way you walk, the way you sit, the way you think.”

Depp Was Almost Unrecognizable InTusk

Photo Credits: A24

In the 2014 comedy/horror film Tusk, Johnny Depp plates Guy Lapointe, trading his signature dark locks for long tendrils of light brown hair, full bushy goatee, graying unkempt eyebrows, moles, wrinkles, a fake nose and a noticeably thicker midsection. Unfortunately, the film was a total flop, earning only $38,000 at the box office and an average rating of 4 stars.

Matt Damon Shocked Everyone In The Informant

Photo Credits: Warner Bros.

Matt Damon shocked audiences when he came out with The Informant in 2009. The actor packed on somewhere between 20 and 30 pounds. To achieve his doughy physique he binged on Doritos, McDonald's and lots of beer with little to no exercise. He described this phase of letting himself go as "absolute heaven." He really enjoyed not going to the gym and eating whatever he wants.

Bale Does It Again

Photo Credits: Columbia Pictures

For the film American Hustle, Bale packed on over 50 points in order to achieve the perfect weight for his character. He also shaved his head and grew out his beard to have a rather grimy look. In order to put on the weight, he says he ate a lot of donuts, cheeseburgers, and just about anything that he could get his hands on.

Portman Wasn't The Only One That Struggled For Black Swan

Photo Credits: Fox Searchlight Pictures

Mila was offered the role of wild child prima ballerina TK in Black Swan without even auditioning. However, that also meant that she had her work cut out for her in order to prepare her body. Kunis trained four hours a day, seven days a week, for seven months. She explains, “I had one day off on my birthday and a half day off for the Emmys and the Golden Globes…by the end I was 95 pounds.”

Jake Gyllenhaal Put In Work For Southpaw

Photo Credits: The Weinstein Company

For the 2015 film Southpaw, Gyllenhaal bulked up from 145 pounds to 175 in just six months. To prepare for his role he trained with a real boxing coach, Terry Claybon. His workout regimen consisted of at least 2,000 sit-ups a day, push-ups, dips, flipping 350-pound tires, and running eight miles five days a week. He trained seven days a week for three hours in the morning, and three hours at night.

Chris Pratt Made Jaws Drop

Photo Credits: Marvel Entertainment

Chris Pratt went from a chubby, funny guy in Parks and Recreation, to a total stud almost overnight for his role in 2014 action film Guardians of the Galaxy. In just six short months the actor dropped 60 pounds. Doing a mixture of P90X, running, kickboxing, a triathlon and what he describes as "Three or four hours a day of just consistent, hard work," he was able to shed the weight quickly.

DeNiro Had A Major Transformation In Raging Bull

Photo Credits: United Artists

The Hollywood legend packed on the pounds for his portrayal of boxer Jake La Motta long gone from his glory days in the 1980 film, Raging Bull. In just four months, DeNiro but on 6o pounds of weight. Apparently, in order to do so, all he did was go vacationing, eating his way throughout Europe. Doesn't sound so bad!

Christian Bale Is A Psycho

Photo Credits: Lions Gate

In the film American Psycho, Christian Bale underwent a crazy physical transformation. He credits this role with teaching him the workout foundations he would later use during his Batman bulking-up days. But it was also his hardest transformation. Bale says, "Not including The Machinist, Rescue Dawn or The Fighter – where I had to lose weight – my role for American Psycho was my most restrictive diet-wise. There were no cheat meals. It was all lean protein. No sugars, good fats and low carbs."

Cate Blanchett Put In A Lot Of Effort To Become Bob Dylan

Photo Credits: The Weinstein Company

In order to play a male in the Bob Dylan biopic, I'm Not There, actress Cate Blanchett had to put in some effort. It's clear that she was willing to put in the effort, considering how good her performance was. Blanchett knew the role would be tough, so she learned guitar and would shove a sock down her pants to practice a manlier walk.

Philip Seymour Hoffman Was A Convincing Truman Capote

Photo Credits: United Artists

While Philip Seymour Hoffman may not be your first guess at who would portray author Truman Capote, but they couldn't have chosen a better actor. Hoffman spent hours watching and listening to interviews so he could perfect all of his mannerisms and get his unique voice correct.

Jared Leto Let Himself Go To Play John Lennon's Killer

Photo Credits: Peace Arch Entertainment

In the film Chapter 27, Jared Leto plays Mark David Chapman, John Lennon's murderer. To play the role, Leto gained 69 pounds and did so by eating microwaved pints of ice cream with olive oil and soy sauce every night to gain the weight. After filming was done, Leto said it took more than a year to feel “semi-normal” again.

Tom Hanks Struggled To Lose Weight In Cast Away

Photo Credits: Twentieth Century Fox

Althoguh it isn't always discussed, Tom Hanks had a difficult time losing weight and keeping it off for his role in Cast Away. In order to prepare for the role, he had to lose 50 pounds as well as grow out his beard and hair, which explains why there was a one year halt in production.

Preparing For G.I. Jane Was No Joke

Photo Credits: Buena Vista Pictures

In G.I. Jane, Demi Moore plays the Luitnenant Jordan O'Neill, the first female to ever undergo Navy Seal training. In order to make the film as realistic as possible, Moore, as well as the others, underwent specialty military training. She even shaved her head in order to stay in character. Moore also performed the majority of her own stunts although she was offered a stunt actor.

Chris Hemsworth Might Be The New Christian Bale

Photo Credits: Warner Bros.

After bulking up bg time to play the son of Odin in Thor, Chris Hemsworth had to shrink back down again in order to be in In the Heart of the Sea. Before and during filming, Hemsworth was on what he called the "lost at sea diet," eating no more than 500 calories a day. However, after filming ended, he got right back into the gym for Thor: Ragnarok.

Hugh Jackman Was Kin And Bones In Les Miserables

Photo Credits: Universal Pictures

While preparing for his role of Jean Valjean, he went from his Wolverine physique, all the way down to a starving French prisoner. At one point, he went 36 hours without food or water, leading him to fall ill. He was also experiencing grouchiness on set, which he called a small price to play for such a notable role.