Credit: Gregg DeGuire/Wireimage

For fans of Charlie Hunnam and his portrayal of the morally compromised Jax Teller on FX’s Sons of Anarchy, the news that he will assume the naughty role of Christian in the film adaptation of 50 Shades of Grey probably came as, well, a massive surprise.

It certainly prompted a few jaw drops on the drama’s North Hollywood, CA. set. “When he told me that it was happening or that he was considering it I just howled. I mean I think we all did. We’re all like, what?” says Maggie Siff, who plays Jax’s savvy wife Tara. “And then I talked to him seriously about it. I think he’s very brave to do it. He doesn’t do anything unless he feels it deep down. He’s not going to do something because all of his agents are telling him to do something. That’s what makes me think it stands a chance of being really, really great. If he has that conviction going in, then you know it’ll be great.”Katey Sagal (Gemma) had additional words of praise for Hunnam. “I’m really proud of him,” she told EW. “The choice was not an obvious one for him. But for good or bad, he will throw himself 100 percent in. I don’t know if I want to see all that, but maybe.” Creator Kurt Sutter echoed the sentiment for his young star. “We’re thrilled for Charlie. He works hard, constantly challenges himself and his craft. He is a star, in all the right ways.”

For his part, Hunnam speaks humbly about starring opposite Dakota Johnson in the movie that will be released on Aug. 1, 2014.

“There are so many fans of that book and I know that on the surface, I’m probably not what everybody imagined,” the actor admits. “Because reading is so personal and people bring a character to life in their imagination, they feel ownership over that character. That’s daunting if I allowed myself to think about it too much. I’m taking it very seriously and intend to explore the nature of who this character is, what motivates him—and also dress up nice and look good in those suits.”

For more on Sons of Anarchy, pick up the latest issue of Entertainment Weekly, on sale Friday.

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