Some eagle-eyed fans have apparently beaten George R.R. Martin's Game of Thrones.

Speaking at the Edinburgh International Literary Festival, the author of the wildly popular A Song of Ice and Fire series, better known as Game of Thrones, admitted that readers have pieced together evidence from his first five books to correctly guess how the epic story will end.

"So many readers were reading the books with so much attention that they were throwing up some theories and while some of those theories were amusing… and creative, some of the theories are right," Martin said.

"At least one or two readers had put together the extremely subtle and obscure clues that I'd planted in the books and came to the right solution."

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Despite the series' conclusion being somewhat compromised, Martin said he remains adamant about his plans to keep the story moving forward in the same direction.

"I wrestled with [changing the ending] and I came to the conclusion that changing it would be a disaster, because the clues were there," Martin said. "You can't do that, so I'm just going to go ahead.

A handful of dedicated fans are not the only ones besides Martin who know how the series will end, however.

In the March issue of Vanity Fair, David Benioff, the co-creator of the hit Game of Thrones television series, revealed that he and D.B. Weiss spent a week with Martin in order to get a feel as to how the series would end.

The reason behind Benioff and Weiss meeting with the author was the growing concern that the television show will run out of source material as Martin continues to work on the sixth book in the series, titled Winds of Winter. The show recently completed its fourth season on HBO.

"We don't know if we are going to catch up and where exactly that would be," Benioff told Vanity Fair. "If you know the ending, then you can lay the groundwork for it. And so we want to know how everything ends. We want to be able to set things up."

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Along with earning critical acclaim and attracting a dedicated viewership, Game of Thrones has brought an influx of fan requests to Martin, who insisted he will not succumb to pressure from his readers and viewers.

"I don't think I can insert things just because everyone wants them," Martin said. "If it was a democracy, Joffrey would have died much earlier than he did."

While readers rabidly obsess over his books, Martin has gained a reputation for being a notoriously slow writer.

The first book in the planned seven-volume series, Game of Thrones was released in 1996 and the most recent entry A Dance with Dragons hit shelves in 2011. Martin drew the ire of fans after taking six years between the release of the fourth and fifth books.

Despite receiving some backlash, Martin says his goal is to continue to provide compelling literature for the masses.

"I hate predictable fiction as a reader, I don't want to write predictable fiction," Martin said. "I want to surprise and delight my reader and take them in directions they didn't see coming."

Game of Thrones Season 5 will premiere in 2015 on HBO.