'Game of Thrones' Prequel Series Set During Dance of the Dragons War? George R.R. Martin Hints Show Will Follow Targaryens

In a new blog post, A Song of Ice and Fire author George R.R. Martin drops a major hint about upcoming prequel series HBO is developing for release after Game of Thrones comes to an end with this year's Season 8.

"Speaking of television, don't believe everything you read. Internet reports are notoriously unreliable," Martin wrote, before clarifying the state of in-development Game of Thrones prequel series and spinoffs. "We have had five different Game of Thrones successor shows in development (I mislike the term 'spinoffs') at HBO, and three of them are still moving forward nicely."

While Martin doesn't say as much, his description implies that two of the potential Game of Thrones prequel series have been abandoned, or at least tabled, for now. One of the three shows still moving forward is further along than the others, with casting, plot details and more already announced. It will be set in the Age of Heroes, when the ancestors of the major houses of Westeros first faced off against the White Walkers. That series is not yet officially titled The Long Night , but that's certainly the title Martin prefers for it.

"The one I am not supposed to call The Long Night will be shooting later this year," Martin wrote. "Two other shows remain in the script stage, but are edging closer."

While Martin didn't share any details from the other two series—"What are they about? I cannot say," he wrote—he did drop a substantial hint regarding what viewers should expect from the other prequel series in development.

"Maybe some of you should pick up a copy of Fire & Blood and come up with your own theories," Martin wrote.

One of the "Game of Thrones" prequel series will follow the Targaryens, George R.R. Martin hints in a new blog post. HBO

Fire & Blood is Martin's New York Times bestselling history of the Targaryen dynasty, beginning with Aegon's Conquest of Westeros, three hundred years before the events of Game of Thrones. The book covers several key eras in the history of Westeros, including the civil war known as the Dance of the Dragons.

With multiple generations of Targaryens detailed in Fire & Blood, we can't be certain what is under consideration for one or both of the HBO series joining The Long Night, but the Dance of the Dragons might just be the marquee event described in the book. During the Dance of the Dragons, the children of Viserys I, the fifth Targaryen to sit on the Iron Throne, fought to be his successor. The resulting war raged across Westeros and featured dragon battles, regicide, feuds within the Kingsguard and a sneaky rat-catcher named Cheese.

Whatever period of Westeros history HBO plans to dramatize, Martin has at least revealed that one or both of the unannounced Game of Thrones prequel series will take place hundreds of years after The Long Night series.

For more on the early history of the Targaryens, check out George R.R. Martin's "Fire & Blood: 300 Years Before a Game of Thrones." Bantam

In the same post, Martin also shared his thoughts on other shows in the HBO lineup. "I am enjoying the hell out of the new HBO drama Gentleman Jack," GRRM wrote. "And of course, Veep is as funny as ever… much funnier than real politics."