Charlie Hunnam just couldn't be a major TV star and Christian Grey all at once.

The "Sons of Anarchy" star explained that he had to drop out of the erotic film "Fifty Shades of Grey" after he had a "nervous breakdown."

"I wouldn't have signed up in the first place if I didn't want to do it," he told Moviefone. "It was a really, really difficult time in my life."

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Sadly, Hunnam is just one man, and his schedule just wasn't allowing him to put in the time needed for such a role. "Sons of Anarchy" was wrapping up production later than expected and he was also scheduled to work on Guillermo del Toro's "Crimson Peak."

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"I was going to finish "Sons" at like 11 p.m. Friday night, get on the plane Saturday morning to Vancouver for "Fifty," missing the whole first week of rehearsal and start shooting Monday morning," he explained. "And I was going to shoot that film, wrap that on the Wednesday and the following Monday I was going to start shooting "Crimson Peak" in Toronto. I just had like ... frankly, something of a nervous breakdown."

That's when the 34-year-old had to make a major decision. "I just said, 'I can't ... I can't," he recalled. "To fail on such a grand scale -- because "Fifty's" going to be massive, it's going to be huge. I really didn't want to fail on such a grand scale and I just couldn't transition from Jax Teller (his "Sons of Anarchy" character) to Christian Grey in 48 hours. I bit off more than I could chew and it was painful. I loved the character and I wanted to do it.

He added of giving up the part, "It was just a s**t situation. I was really, really, sorry to do it. It was one of those damned if you do, damned if you don't situations."

The role of Christian Grey ended up going to Jamie Dornan. See him seduce Dakota Johnson, who plays Anastasia Steele, in the steamy "Fifty Shades of Grey" trailer:

The book-turned-movie hits theaters Feb. 13, 2015.

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