Why George R.R. Martin Will Not Participate in 'Game of Thrones' Season 5

He's got bigger fish to fry ... or kill.

— -- To the chagrin of fans, George R.R. Martin will not be involved in the upcoming "Game of Thrones" season 5 when it returns filming for HBO, the author said.

The man who penned the books usually contributes in some way, but told Vulture he's sitting this one out to finish his next book, "The Winds of Winter."

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"I’ve got to finish the book 'The Winds of Winter,'" he told the website. "So I don’t think I’m going to do a set visit this year, sadly."

When asked if he'd write an episode this year, he said, "Not this year, no -- once again because I have this book to finish."

Martin has even backed off when it comes to casting. At Comic-Con this past weekend, nine new actors were added to the series, but it doesn't look like he had much of a hand in that either.

"In the earlier seasons I was much more involved with casting," he said. "I would review tapes and comment, but that’s a time-consuming process."

He continued, "And at this point, we’re five seasons in, we have the best casting director in the business in Nina Gold, David [Benioff] and Dan [Weiss] have been running the show, and it’s a well-oiled machine, so it really doesn't need me down there with the oil can squeaking at the wheels."

Martin closed the interview by saying "My stress is still the books."