Tom Hiddleston has starred in blockbuster films such as ThorThe Avengers and War Horse, but the actor says that playing country music legend Hank Williams in the forthcoming biopic I Saw the Light proved to be one of his most challenging -- and most fulfilling -- roles yet.

"It took me a while to fully say yes [to the role], because I knew that once I said yes, I was going to have to cancel everything else in my life and make this a priority, because Hank Williams means so much to so many people. He’s an icon, and he’s left a legacy in American music, which is evergreen," Hiddleston tells The Boot. "And I knew once I said yes, the seriousness with which I was going to take it in terms of changing the way I looked, changing the way I sounded, getting under the skin of his particular artistic spirit and the music and the culture, and I’m honoring that, doing right by him."

The selection of the British actor for the role was met with some opposition early on; critics, including Williams' grandson, Hank Williams III, claimed that Hiddleston wasn't the best choice for the iconic role. But the naysayers only propelled the actor to work harder than ever before.

"A great weakness of mine is that, when people tell me I can’t do something, it’s a red rag to a bull; it makes me want to do it even more ..." Hiddleston explains. "... I always find it’s a slightly sort of sensationalizing debate every time a Brit plays an American or an American plays a Brit."

To refute the critics, Hiddleston spent months working with the film's music director, Rodney Crowell, to be able to play his role as authentically as possible. Crowell, for his part, says he's "as respectful of [Hiddleston]'s work ethic as I’m mystified by his transformational skills. Without a doubt, the filmmakers chose the right actor for the job.”

"It was challenging. Of course it was," Hiddleston concedes. "Doing something like this isn’t easy, but it’s the best kind of work. It’s the kind of work you dream about as an actor."

I Saw the Light is now playing in theaters nationwide.

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