In "Ghost Dog: The Way of the Samurai," Forest Whitaker was a samurai hitman quietly assassinating members of the mob. In "The Last King of Scotland," he was the late Ugandan dictator Idi Amin, overthrowing a government then brutally murdering thousands of his own people (his performance nabbed him a Best Actor Oscar). And in "Bird" he was jazz great Charlie Parker, playing the saxophone and struggling with substance abuse.

These are the types of performances Whitaker is known for: complex roles that require an extraordinary level of intensity and zeal. But in person, Whitaker isn't the towering, intimidating presence you might expect. Instead, he feels closer to a fatherly next-door neighbor, one who's gracious, open-hearted, and a bit introverted.

Coincidentally, these are the same characteristics Whitaker shares with Cecil Gaines, the man he portrays in his latest movie, "Lee Daniels' The Butler." While his Gaines doesn't chew the scenery in quite the same way as his previously mentioned portrayals, this role may go down as one of the actor's most memorable.

The film, based on the true story of Eugene Allen, is about the life of a White House butler, who served his country for more than 30 years under seven different presidents. (The basis for the film stems from a 2008 Washington Post profile on Allen.)

The role proved to be a unique undertaking for Whitaker, which is saying something; the actor is known for his dedicated and unorthodox methods of getting into character -- for "Bird," he holed up for months in a loft with only a bed, a couch, and a saxophone; and for "The Last King of Scotland" he learned Swahili and the accordion, an instrument Amin played frequently.

So what method did Whitaker use to find his way into Gaines?

"I always break a character down, but I've never broken a character down as specifically as this one," Whitaker explained to Moviefone -- and he wasn't joking. "I obviously had to figure out the accent, so I worked on the accent; I worked on understanding the history and geometry of it. I had to work on movement of the character. I had studied with a butler coach -- I actually studied for quite awhile, just learning how to serve properly and set formal dining tables; I did that for weeks."

Whitaker also made sure to map out his character's aging process, taking notes and making graphs of Gaines's body, which broke down the character's physical and emotional state as he got older (in the film, we see Whitaker play Gaines from ages 30 to 96).

"There was a breakdown of every period in his life, and all the historical and emotional events inside of it," Whitaker said. "It was a breakdown of all my work and how I specifically say what I am going to do and what I am going to look for in this scene -- where the pain is in my body, how I am going to speak, what I am going to dress like, what kind of props I need the director to get because I want to show certain things -- just really detailed, down to his furniture."

Besides delving into the complications and intricacies of learning about his character's aging process and emotional state (and what type of furniture he'd have in his house), Whitaker also wanted to discuss his role with current and former White House butlers. While this is usually standard practice in the movie business -- an actor shadowing or interviewing a person with the type of job their character has -- Whitaker faced some complications.

"There was not only hesitation, there were absolute no's," said Whitaker, of asking butlers about their time at 1600 Pennsylvania Avenue. "They wouldn't talk about what they've done with the presidents or what the presidents do privately or any of those things, so it wasn't easy to get that kind of research."

Luckily, Whitaker eventually got the information he needed, it just took a bit of coaxing and additional research. After he finished, he says he just fell into the role: "I kind of just jumped off the edge."

But there was still one major challenge left to unlocking Cecil Gaines, one that took place during shooting: having to play different ages of the character in one day. This sounds rather difficult, but for someone like Whitaker, who prunes and picks his way through each of his character's psyches, he makes it seem like a piece of cake.

"All of a sudden I am playing a 90-year-old, but now I am going to do this 30-second scene where I am, like, 28. So I have to know how I walk and where I am coming from, what just happened, what I am thinking," Whitaker said. "It became simpler because I figured out each one of these experiences would be the reason why I would age or move a certain way. So if I would move from that experience, physically, then I would immediately carry all those things. I had never done it before. It was the first time I realized it was possible."

Whitaker has appeared in almost 75 films. Like most actors who've been around as long as he has, he's had his fair share of duds. But "The Butler' feels like a culmination of his talents -- a performance that mixes both dedication and clarity, two attributes that are tough to find in Hollywood's current crop of leading men.

Not only that, Whitaker does this in a film that encompasses the entire Civil Rights struggle, which is no small task. As his "Butler" co-star Oprah Winfrey said about the movie and his performance: "[Forest] is the soul of it. It's such a holy, sacred thing that he did. He went into that energy space that actually is the legacy of the ancestors. He tapped into that feeling."

When you've gotten praise from Oprah, you know all that hard work has paid off.

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Lee Daniels' The Butler Movie Poster
Lee Daniels' The Butler
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After leaving the South as a young man and finding employment at an elite hotel in Washington, D.C.,... Read More