'Game of Thrones' EPs: Season 5 "Diverges a Bit More" From the Books (Video)

How far is Game of Thrones season five willing to go?

Among the most hotly discussed topic among A Song of Ice and Fire book readers is the certainty that the HBO series will conclude before George R.R. Martin's book series — and what that means for some of the series' big reveals.

The HBO series took a major step ahead of the books last year when it revealed what the White Walkers do with Craster's babies. Season five still has plenty of material to draw from, with much of Martin's fifth book, 2011's A Dance With Dragons, not having yet been depicted on screen. Showrunners David Benioff and D.B. Weiss do say the season continues a trend of making tweaks when adapting the ever-more sprawling books.

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"I think it's fair to say every season diverges a bit more from the previous one," Benioff tells The Hollywood Reporter

Season one was the most faithful direct adaptation of a book, following Martin's 1996 novel A Game of Thrones closely. As the books grew more complicated, the showrunners made more tweaks, occasionally killing characters who didn't die in the books or shifting storylines around — such as Theon (Alfie Allen) remaining a constant in the TV series, while he disappears for quite some time in the books.

"As the books go on, they get bigger and bigger with more and more characters, which we felt we'd capsize the show if we put in every single character from the books. We'd have ten seconds for each character per show," says Benioff, who notes that the fourth book, 2005's A Feast of Crows, would be "impossible to be faithful to because half the characters would be missing."

That book, along with Dance With Dragons, cut out key characters.

Though Martin has said characters will die in season five who don't die in the books, the showrunners are neither confirming nor denying that.

"It totally depends," says Weiss of deciding how to kill of a character who lives in the books. "Sometimes it's what we think is best for the story."

Stay tuned to The Live Feed for much more from Game of Thrones in the days to come.

Game of Thrones season five premieres at 9 p.m. Sunday on HBO.