Which Book Will 'Game Of Thrones' Season 6 Be Based On? There's Actually A Lot Of Source Material Left To Adapt

Season 5 of HBO's Game Of Thrones will always be remembered as the year the epic fantasy series finally caught up with its source material. Since Season 1, the public has watched with increasing interest as the show devoured George R.R. Martin's A Song Of Ice And Fire series one novel at a time, with no sign of further entries being published by the notoriously slow author. Finally, the ticking clock ran down. The latest season of Thrones pulled most of its inspiration from the fourth and fifth books in Martin's series — A Feast For Crows and A Dance With Dragons — which begs the question: which Game of Thrones book will Season 6 be based on?

The final Ice And Fire books, titled The Winds Of Winter and A Dream Of Spring, still have no release dates set. In their absence, it seems like next season of Thrones will largely consist of original material, right? Not so fast. Although Season 5 did adapt the bulk of AFFC and ADWD, there's actually still some storylines left to be covered... and judging by recent casting calls for Season 6, showrunners David Benioff & D.B. Weiss plan to finally tackle those dangling plot threads.

Quite contrary to having no source material to pull from, Game Of Thrones Season 6 will actually be based on quite a few of Martin's novels, like... [spoilers ahead]

A Feast For Crows

When Season 5 began, it became apparent that Benioff & Weiss had decided to trim some of the fat from Martin's novels, excising unnecessary subplots and combining old characters with new ones wherever possible. (See: Tyrion's condensed journey through Essos, and Jorah contracting greyscale instead of Jon Connington — a character who doesn't even exist on the show.) However, the leaked casting notice makes mention of several characters which indicate that perhaps Benioff & Weiss weren't cutting these subplots as we all thought... they were merely saving them for later.

One such subplot concerns the Greyjoys and their struggle for control of the Iron Islands after the death of King Balon. (A death which has yet to occur on the show.) His daughter Asha (Yara on the show) as well as his brothers Euron and Victarion all vie for his crown at a "Kingsmoot." Another subplot concerns Brienne's and Jaime's separate travels through the war torn Riverlands of Westeros. Yet another concerns Sam's travels to Oldtown to become a maester at The Citadel.

With mentions of a "pirate" (clearly Euron) and a "priest" (likely a septon Brienne encounters on the road) in the casting call, as well as Sam finally departing for Oldtown in the Season 5 finale, all of these storylines are on the verge of a major comeback in Season 6.

A Dance With Dragons

AFFC and ADWD are essentially two halves of the same book; each only contain half of the characters from the Ice And Fire series, while events in the two novels occur simultaneously. Since ADWD contains most of the saga's main characters — Tyrion, Jon, Dany — it's actually more fully adapted than its predecessor. But, there's still a bit of material left within its pages Benioff & Weiss haven't had time to explore yet.

Bran only has three point-of-view chapters in ADWD, and by the end of Season 4, the show had already covered two of them. This is why Benioff & Weiss decided to have the character sit out for an entire season; there simply wasn't enough material left to last for 10 episodes. But Bran will presumably return next season, and his final chapter, focused on his training with the Three-Eyed Raven, will need to be adapted.

Season 5 did have one glaring omission: the story of Young Griff, aka Aegon Targaryen, the son of Prince Rhaegar and Elia Martell who was supposedly killed during the Sack of King's Landing. In ADWD, it's revealed that Aegon survived, was spirited away into hiding, and is now on his way to join his aunt Daenerys in Meereen. (And by "join" I mean "marry" since that's just what Targaryen relatives do.) When he finds out she's already married Hizdahr Zo Loraq, he changes his mind and reverses course for Westeros, which he intends to conquer on his own.

And, while most of the major plots from ADWD reached their endpoints (Jon, Dany, Cersei), the season didn't quite reach the novel's epilogue... in which Varys returns to King's Landing and assassinates Kevan Lannister because he was too good at ruling, and Varys needed Westeros destabilized in order to pave the way for Dany's triumphant return.

The Winds Of Winter

While there are still plenty of subplots from AFFC and ADWD left to tackle, there are even more characters who are caught up with their book counterparts and will be delving into Book 6 territory next season. Some of them are already there: Stannis allowing Melisandre to burn Shireen alive hasn't happened yet in any of the books, although Benioff & Weiss made it clear in HBO's "Inside The Episode" that this particular plot point was given to them by Martin himself from his upcoming book.

Before Season 5 even started, the showrunners confirmed that the show would begin spoiling the books. While Martin probably hasn't told them every single detail of TWOW, he's not exactly making them fly blind, either. "We know where things are headed," Benioff said, confirming that the author has given them at least a vague outline of events to come. (Of course, there's always a chance that Martin could have his sixth book published before next season premieres, but that would only make a difference for the viewers, not the writers. Season 6 begins filming next month, which means most of the scripts are probably already in the can.)

Original Material

Naturally, Benioff & Weiss will have to fill in the outline given to them by Martin with material of their own. While it's hard to tell the difference between TWOW spoilers and original material without Benioff & Weiss specifically telling us (like they did with Stannis burning Shireen), there have already been some storylines that are clearly not from Martin's books since they so drastically depart from where their analogous characters are located: Jaime and Bronn's ill-fated trip to Dorne; Brienne and Podrick's sojourn outside Winterfell; Tyrion arriving at Meereen before Dany rides away on Drogon. However, as we enter uncharted territory next season, the distinction between spoilers and fabrications will become increasingly hard to discern.

A Storm Of Swords

I would be remiss if I didn't point out that there's technically still an un-adapted chapter from Martin's third book — and a pretty major one at that. For whatever reason, Benioff & Weiss chose to never translate the epilogue of A Storm Of Swords, in which it's revealed that the Red Priest Thoros of Myr has resurrected the corpse of Catelyn Stark, who is now a vengeance-seeking zombie called Lady Stoneheart. While the fan-favorite figure has failed to materialize for three season finales in a row now (even though I was convinced she would finally show her face this year), there's always a chance she could still pop up in Season 6. As the casting call reveals, the show will be journeying back to the Riverlands, which is Lady Stoneheart's domain.

Keep the flame of hope alive, Lady Stoneheart fans!

Images: HBO (2); Helen Sloan/HBO (4)