Name: Meryl Streep
Film: Music of the Heart (1999)
File Under: Musical Ambition
Meryl Streep learned how to play the violin for her role as a violin teacher by practising six hours a day for four weeks.

See Also: Sean Penn, Sweet and Lowdown (1999)
Penn learned how to play jazz guitar to make his performance as an egotistical guitarist in Woody Allen's Sweet and Lowdown as realistic as possible.

Name: Al Pacino
Film: Serpico (1973)
File Under: Occupational Hazard
So immerced in his role as an undercover cop in Serpico was Al Pacino, that he actually pulled over a truck driver and attempted to arrest him for exhaust pollution.

See Also: Robert De Niro, Taxi Driver (1976)
In preparation for his role, Robert De Niro worked twelve hour shifts for a month as a cab driver.

Name: Martin Sheen
Film: Apocalypse Now (1979)
File Under: Drunk on the Job
Filmed during a low time is his career, Martin Sheen was actually intoxicated during the opening scenes where his character, Captain Willard, breaksdown in a hotel room and smashes a mirror with his fist, resulting in real blood loss.

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See Also: Nicolas Cage, Leaving Las Vegas (1995)
In preparation for his Oscar winning role as a suicidal alcoholic in Leaving Las Vegas, Nicolas Cage would film himself when he was drunk, sot that he could mimic himself in an intoxicated state.

Name: Dustin Hoffman
Movie: Marathon Man (1976)
File Under: Sports Handicap
To prepare for his role as a marathon runner on the run from Nazi spies in John Schlesinger's Marathon Man, Dustin Hoffman lost 15 pounds (running four miles a day to get in shape for the part) and would run half a mile before filming any scenes that required heavy breathing. Legend has it that co-star Laurence Olivier quipped "Why not try acting? It's a lot easier", but Hoffman has since disputed this story.

See Also: Sylvester Stallone, Rocky series
Stallone's insistence on giving out real hits during his various Rocky bouts cost him dearly when he faced off against Swedish behemoth Dolph Lundgren in Rocky IV, who gave Stallone temporary rib and heart damage for his troubles.

Name: Halle Berry
Film: Jungle Fever (1991)
File Under: What's That Smell?
In her debut film role as a homeless crack addict in Spike Lee's Jungle Fever, Halle Berry decided that the best way to get into her character was by not bathing for two weeks!

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Name: Brad Pitt
Film: 12 Monkeys (1995)
File Under: Give that man a straightjacket!
To get a handle on what it would be like to live in a mental asylum, Brad Pitt volunteered to stay in a Philadelphia mental institution for one day.

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Name: Robert De Niro
Film: The Mission (1986)
File Under: Jungle Fever
Method man Robert De Niro took to his role as a redemptive slave trader in the jungles 18th century Portugal with reckless abandon, often shocking the films producers by jumping around the forests and rocky river beds barefoot before and during production to bring as much reality to his performances as possible.

See Also: Daniel Day Lewis, The Last of the Mohicans (1992)
Unlikely action hero Daniel Day Lewis lived in the wilderness for several months in preperation for his role as the last member of a dying tribe in Michael Mann's The Last of the Mohicans.

Name: Nicolas Cage
Film: Vampire's Kiss (1989)
File Under: Crispy Critters
The forever eccentric Nicolas Cage proved to be an actor of unorthodox principles when he ate a real cockroach during the filming of Robert Bierman's Vampire's Kiss. Three takes were needed for the scene, with a new cockroach provided for each take.

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Name: Daniel Day Lewis
Film: My Left Foot (1989)
File Under: Acting Disability
While playing the role of cerebral palsy sufferer and acclaimed writer Christy Brown, Daniel Day Lewis would refuse to break character between takes and often made his friends ad co-stars feed him. He would also break two of his ribs whilst maintaining the hunched over position.

See Also: Billy Bob Thornton, Sling Blade (1996)
Besides holding that uncomfortable grimace for is role as a partially handicapped man in Sling Blade, Billy Bob Thornton also placed crushed glass in his shoes to keep his characters awkward shuffle consistent.

Name: Robert De Niro
Film: Raging Bull (1980)
File Under: Extreme Dieting
De Niro took his method acting to a new extreme as boxer Jake La Motta in Martin Scorsese's Raging Bull. After achieving a trim figure to play a convincing middle weight boxer, De Niro gorged all over Italy and gained 60 pounds in order to realistically portray LaMotta in the later stages of his life.