By all accounts, actor Forest Whitaker is a gentle bear of a man, a 6-foot-2 father of four with a wide range of films to his credit as both an actor and a director. He’s played jazz legend Charlie Parker in “Bird,” as well as a British soldier with a quirky “girlfriend” in “The Crying Game.” He out-hustled Paul Newman at the pool table in “The Color of Money.” He’s directed the romances “Waiting to Exhale” and “Hope Floats.”

But why’d he want to join the cast of “The Last King of Scotland,” and climb inside the skin of Ugandan dictator Idi Amin, one of the 20th century’s most ruthless, blood-stained despots?

“I didn’t know much about Idi Amin,” Whitaker says over diet Cokes at a Toronto hotel restaurant. “I just had this image of this guy in those military epaulets, this angry beast of a man. I thought it’d be interesting to try to get inside his head and try to understand the situation. I read the book. I thought this would be really challenging for me. If I could find it, if I could catch it, it’d be something real special for me.”

Indeed, Whitaker’s performance is among those that generated the most buzz at last month’s Toronto International Film Festival; and there’s even early talk of a possible Oscar nomination.

“Anytime you try to figure out how a person thinks and feels, his loves, his desires, you start to understand — certainly not justify — his choices, even inside his insanity. Inside his paranoia, some of his choices made sense to me. I associated him with being a soldier who is cornered and who fights back the only way he knows how.”

Whitaker believes in research, and found a wealth of material on Amin. “I started studying in Los Angeles, reading the various books and looking at documentaries. There’s a lot of footage of Amin, because he was quite the showman.” Whitaker even learned Swahili and how to play the accordion, and got both elements into the film.

He also put on 60 or 70 pounds to suggest Amin’s famous girth. (He’s lost it all; Whitaker in Toronto is positively thin.) “And I had to have makeup each day, because Amin is from a region where people have darker skin with bluish tones.”

Whitaker says it was huge help to film in Uganda, where the events took place. “I met people he knew, his family, and generals and cabinet members. And I really tried to explore Uganda.”

The job also inspired Whitaker to explore his own roots, which DNA testing has confirmed are in West Africa. “I wanted to understand what it meant to be African, because I’m an African-American and this was my first trip to Africa. I wanted to understand what it was like to be Ugandan, even though my roots are in Nigeria and other parts of West Africa.”

A Texas native, Whitaker studied operatic singing at the University of Southern California before switching to drama classes. For his first film, he played a high school football player in “Fast Times at Ridgemont High.” Other early efforts include “Vision Quest,” “Platoon,” “Stakeout,” and “Good Morning, Vietnam.”

His early success weren’t without struggles. He’s afflicted with a “lazy eye” condition called strabismus, and had to find filmmakers willing to ignore it.

“The Crying Game” and “Bird” both elevated his stature, and the latter film garnered several awards and Oscar buzz, but, unfortunately, an Academy Award nomination never materialized. More recent roles have included a burglar who threatens Jodie Foster in “Panic Room” and a cop in “Phone Booth,” as well as a recurring role as a cop on TV’s “The Shield.”

Ironically, his often-gritty film roles seem far removed from the fluffier romantic comedies that he’s made as a director-for-hire, films like “Waiting to Exhale,” “Hope Floats,” and “First Daughter.” It’s a contrast he’s noted.

“I’ve decided to really be careful and wait to find the project I’ll do next,” he says. “I want to find something that’s relevant. It’s an interesting time on the planet and I’d like my next film to somehow comment on that, even if it’s indirectly. I want a project that has a little more edge, and is a little more visceral.

”Directing takes a couple of years. That’s why the next one has to be something that’ll drive me.“

Meanwhile, he’s earning some of the best reviews of his career for ”The Last King of Scotland,“ and, once again, he’s hearing Oscar buzz.

”I hope it gets people to come see the movie. And it’s a nice thing when people talk about your work like that. As far as what happens, it’s out of my hands, and I don’t want to live inside it too much, because it can be disappointing if it doesn’t happen.“

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WHITAKER'S WINNERS

U.S. box office for the most successful films Whitaker either appeared in or directed:

• ”Platoon“ ($137.9 million)

• ”Good Morning, Vietnam“ ($123.9 million)

• ”Phenomenon“ ($104.6 million)

• ”Panic Room“ ($95.3 million)

• ”Waiting to Exhale“ ($67 million)

• ”Stakeout“ ($65.7 million)

• ”The Crying Game“ ($62.5 million)

• ”Hope Floats“ ($60.1 million)

• ”Species“ ($60 million)

• ”Phone Booth“ ($46.6 million)