HBO is getting set to debut Season 5 of Game of Thrones on April 12, but the future of the show may be somewhat in question, at least from a story standpoint. HBO has already renewed the series for Season 6, and we reported back in October that the cast members have renewed their contracts through Season 7, but today, The Guardian reports that there are no plans to publish the long-awaited sixth book in George R.R. Martin's A Song of Fire and Ice series in 2015. Here's what the author's publisher, Jane Johnson from HarperCollins, had to say in a statement.

"I have no information on likely delivery. These are increasingly complex books and require immense amounts of concentration to write. Fans really ought to appreciate that the length of these monsters is equivalent to two or three novels by other writers."

George R.R. Martin published the last installment of his A Song of Fire and Ice series, A Dance with Dragons, in 2011, but he is releasing a compilation of his prequel novellas, The Hedge Knight, The Sworn Sword and The Mystery Knight, in an illustrated edition set for release in October. The story takes place nearly 100 years before the events of Game of Thrones, when the Targaryens still held the Iron Throne. However, while we still wait for the sixth book, the HBO series is now essentially guaranteed to catch up to the books.

Season 5 is largely based on the fourth book, A Feast of Crows, and parts of the fifth book. The third book, A Storm of Swords was so plot-heavy that the producers split it into two seasons of the show, but now, with no plans for the sixth book's release on the horizon, it remains to be seen how this will affect the future of the show. Isaac Hempstead-Wright's Bran Stark is actually sitting Season 5 out, since his story in the show has already caught up to his plot in the books.

Season 6 will start production this fall, which will likely air in in the spring of 2016, with the seventh and final season arriving in 2017. Of course, even if George R.R. Martin's sixth book is released in early 2016, it still isn't clear when the seventh and final book, A Dream of Spring, will be released. Both of George R.R. Martin's last two books are said to be between 800 and 1,100 pages long apiece, and with the pace he's been going lately, it's anybody's guess when the last two books will finally be released.

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A recent Washington Post predicted that George R.R. Martin won't release the final book until 2023, or six years after the TV series will end, at its current pace. What do you think about these new developments? Are you upset George R.R. Martin's next book won't be released this year?