Derek Luke says he wasn't immediately attracted to his latest film, "Catch a Fire."

"This was work," he says. "This is not a comedy. This is like every day I would have to learn something new."

In the movie, co-starring Tim Robbins and directed by Phillip Noyce, Luke plays Patrick Chamusso, a real-life player in the revolution against South Africa's apartheid government. As depicted on screen, Chamusso was a peaceful man who became a revolutionary only after he and his wife were tortured during the investigation of a terrorist bombing at an oil refinery. For Luke, an American, it was a major challenge to play the South African native.

"First of all, I'm embodying the whole of South Africa," Luke said. "I'm embodying a new culture. My first film when I played a real-life person ("Antwone Fisher") I just moved from L.A. to Cleveland. This one was a little larger distance, so of course you want to get it right."

Luke, 32, was born in New Jersey. For his breakthrough role in 2002, the title character in "Fisher," Luke helped tell the real-life tale of a troubled man who comes to terms with his past and finds success, and he won an Independent Spirit award for his performance.

Chamusso said he was initially unsure about the decision to have Luke portray him on screen.

"I hadn't seen his work before," Chamusso said. "So, I was thinking of somebody else, like Wesley Snipes, Denzel Washington, Samuel Jackson. ... Then, I saw that this man wants to learn. I opened my heart for him."

Luke said Chamusso had an all-access pass to the set, and the two men spent a lot of time together.

"If Derek had got a script only without seeing me, I don't think he would have done what he did," Chamusso said. "By seeing the real person, it adds more to the actors."

For Luke, having the inspiration for his character so close at hand was daunting. Even more daunting, however, was being one of only a few American actors working on the film.

"For me, those rehearsals were chaotic," Luke said. "For instance, the table read. All these South African actors are there and me and Tim (Robbins) from New York and New Jersey. ... You're trying to master those accents. ... It was intense."