Emmy Rossum's Ultra-Bizarre 'Angelyne' Transformation: 10 Celebrities Who Went to Extreme for Roles

Johnny Depp in 'Black Mass'

Johnny Depp has gone deep into many of his characters, from cartoonish flights of Tim Burton's fancy to swaggering pirates based on real-life rock stars. However, in comparison to Rossum, his most impressive change may have been for Black Mass, where he played real-life mobster James "Whitey" Bulger.

Depp was afixed with bald caps, hair implants, facial prosthetics and colored contacts to completely become Bulger, according to a report by The Guardian. With that in place, it was up to him to deliver the performance behind the makeup. He reportedly studied recordings of Bulger in life, and spoke to people who had known him to get a feel for his personality.

The result was a whole lot of praise for Depp from critics, which stood out among the otherwise middling reviews for Black Mass.

Charlize Theron in 'Monster'

In 2003, Charlize Theron tapped into some dark thoughts in order to play real-life serial killer Aileen Wuornos in Monster. To start, she had to gain 30 pounds of bodyweight — likely an uncomfortable task for a former model. She reportedly did so by eating "Krispy Kremes and potato chips."

Theron also wore crooked dentures for teeth, had her real hair thinned and made ragged and even partially shaved her eyebrows. She had washed-off tattoo ink rubbed on her skin to make it look chapped, and then she tied it all together with a hauntingly realistic performance.

Theron was lauded for this performance, which won her 17 awards, including the Oscar, Golden Globe and Screen Actors Guild Award for best actress in 2004.

Chris Pratt in 'Guardians of the Galaxy'

Fans were shocked when the first act of Guardians of the Galaxy gave them a lingering shot of shirtless Chris Pratt rippling with toned muscle. The actor was known for his goofy comedy work, but he underwent an extensive transformation in the hopes of becoming a superhero.

Pratt did "three or four hours a day of just consistent, ass-kicking hard work" to get into shape, according to a report by Men's Fitness. He lost about 60 pounds in six months.

Pratt was reportedly around 300 pounds when he first auditioned for Guardians. Before that, he was best-known for his role on Parks and Recreation. His change was so drastic that the show actually addressed it in a joke the following season.

Jonah Hill in 'Maniac'

Jonah Hill is well-known for his weight fluctuation on-screen, but no change may be more complete than the one he underwent for Maniac. The actor had slimmed down substantially for his role in 22 Jump Street, only to put 40 pounds back on for War Dogs at the time. When Netflix's Maniac came out, many fans thought they were seeing a brand new side of Hill.

Hill has resisted talking about his weight fluctuation in some interviews over time, particularly in quick press junkets promoting movies. That itself has become a bit of a meme, with fans begging journalists to leave Jonah Hill alone when it comes to his physique.

Natalie Portman in 'Black Swan'

Natalie Portman was already relatively thin when she took on the role of The Swan Queen in Black Swan. That makes it that much more shocking that she lost 20 pounds for the role, giving her the waif-thin look associated with the movie.

Portman was 29 years old at the time, making it even harder for her to attain this physique than for ballerinas that train relentlessly from childhood. She reportedly rehearsed 8 hours per day, eating mostly carrots and almonds. She even dislocated a rib while practicing. At the same time, she developed the two distinctive personas she plays in the movie, selling the psychological thriller like no one else could.

"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," she later said, according to The Independent.

Portman won an Oscar for the role, and it elevated her to the next level of stardom. After coming up through the Star Wars prequel trilogy and other lighter fare, Black Swan left no doubt that Portman was a serious Hollywood actor.

Tom Cruise in 'Tropic Thunder'

Not all big transformations have to come from dramas and historical films, as Tom Cruise proved in Tropic Thunder. The famously handsome action star played a balding, pot-bellied and hairy-chested studio executive named Les Grossman in the movie, to the shock and delight of many Mission Impossible fans.

Cruise reportedly wore a fatsuit for the role rather than gaining wait himself. He also wore over-sized prosthetic hands, and covered his arms and chest in fake hair.

Cruise's role was kept top secret during the promotion of the movie, allowing fans to see it as a big surprise in the theater. Admittedly, it was probably over-shadowed by Robert Downey Jr.'s "transformation" in the same film, where he wore blackface for the entire movie. It seems safe to assume history will look back more fondly on Cruise's role.

Christian Bale in 'The Machinist'

No discussion of actor transformations would be complete without a mention of Christian Bale in The Machinist. The actor risked his health is a serious way to play Trevor Reznik, reportedly subsisting on a diet of less than 500 calories per day.

Bale lost about 63 pounds for the role, eating one apple and one tin of tuna per day. He curbed his appetite further with black coffee, cigarettes and whiskey, according to a report by Diethics. By the end, the 6-foot tall actor reportedly weighed about 120 pounds.

Bale put on an unforgettable performance in The Machinist, and despite his discomfort, he did not stop changing his body from role to role. After this movie, he gained almost 100 pounds back to play Batman, and later he gained even more weight to play former Vice President Dick Cheney in Vice.

Demi Moore in 'G.I. Jane'

Obviously male actors can and have bulked up to play muscular action heroes, but in 1997 Demi Moore proved that women can do the same. She reportedly underwent real Navy SEAL training to become Lieutenant Jordan O'Neil in G.I. Jane, waking up at 4 a.m. to get her workout in before filming began, according to Pop Workouts.

The transformation is all the more incredible when remembering that, up until then, Moore was best-known for highly feminine roles like Hester Prynne in The Scarlet Letter or Erin Grant in Striptease. Compared to those, the head-shaved military soldier was a striking change, and fans applauded Moore for it.

Eddie Murphy in 'Coming to America'

Eddie Murphy was hard to recognize when he played the elderly Jewish man Saul in Coming to America. Saul was a part of the chattering chorus in the barbershop in the movie, but he was also one of the most obscure characters played by Murphy.

Murphy and the movie's director, John Landis reportedly decided to have him play Saul in response to the flood of white comedians using blackface at the time. Years later, Dave Chappelle would expand on this in The Chappelle Show, and then after that Keegan-Michael Key and Jordan Peele would do the same.

Murphy is now working on a long-awaited sequel, Coming 2 America, and fans can only hope for Saul to reappear in the movie.

Daniel Radcliffe in 'Jungle'

Before he was even finished growing up, movie-goers were pitying Daniel Radcliffe, assuming he would never outgrow the type-casting of the Harry Potter franchise. He has since surprised them all with some truly strange roles, many of which make it hard to believe he really played The Boy Who Lived.

The biggest of these may be Jungle, where Radcliffe played real-life Israeli adventurer Yossi Ghinsberg. Ghinsberg was stranded in the Amazon rainforest in Bolivia for three weeks back in 1981, and survived on foraged fruit and eggs. Ghinsberg lost about 35 pounds during his isolation, and Radcliffe did the same for the role.

"I'm not a method actor, but it would seem weird if I was playing this guy stuck in the jungle and going home, having a lovely steak dinner at the end of the day," Radcliffe told Esquire.