Charlie Hunnam famously walked away from the Fifty Shades of Grey movie just weeks before it was set to go into production in Canada. He was swiftly replaced by Jamie Dornan, though there was debate as to Hunnam's reasons for quitting: some suggested a disagreement over the script, others cited concern over having to replicate the book's more explicit passages.

Charlie HunnamCharlie Hunnam couldn't juggle his Sons of Anarchy schedule with filming on Fifty Shades of Grey

Now, speaking to Men's Health, the Sons of Anarchy actor confirmed it was the shooting schedule that prevented him from fully committing to the role.

"I was going to finish playing a psychopath who'd just lost his wife [in Sons], and five days later I'd be on set playing Christian Grey," the 34-year-old told the magazine's December issue. "I was like, 'This is going to be a f---ing disaster.' It was the opposite of how I've tried to ground my career, not stretch myself too thin, and always do my homework."

Jamie DornanIrish actor Jamie Dornan eventually snagged the role of Christian Grey in Fifty Shades of Grey

"...there's a tendency in this Hollywood machinery to take on too much," he added, "You end up not being able to give everything you want." He learned early on that that kind of lifestyle doesn't work for him. "Since I was young, I've been aware that I need time to myself to process everything."

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Hunnam had hinted at scheduling difficulties when speaking to Us Weekly back in August, saying, "It was a really, really difficult time in my life," and adding that he suffered "frankly, something of a nervous breakdown."

Now, it is Irish actor Dornan who will star opposite Dakota Johnson in Fifty Shades of Grey set to hit theaters on Valentine's Day 2015.

Meanwhile, Hunnam is believed to have been cast as King Arthur in Guy Ritchie's intended big-budget franchise.  He will make his debut in the role in Knights of the Roundtable: King Arthur, slated for release on July 22, 2016.

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