EXCLUSIVE: Hold your dragons, Game of Thrones fans, another prequel of the hugely popular fantasy series is eyeing a green light. I’ve learned that HBO is close to giving a pilot order to a GoT prequel from author and GoT co-executive producer George R.R. Martin and Colony co-creator/exec producer Ryan Condal, which is set 300 years before the events in Game of Thrones and tracks the beginning of the end for House Targaryen. The network declined comment.

Courtesy WME/Linda Carfagno

Created by Martin and Condal and written by Condal, I hear the project is based on the Fire & Blood book by Martin and has been in the works at HBO since last fall.

According to sources, the Condal/Martin project is not a sixth GoT prequel. I hear it represents a brand new take on a world originally tackled by Bryan Cogman in one of the five GoT prequel scripts commissioned by HBO in 2017. Former GoT co-executive producer Cogman confirmed in April that his prequel idea was not going forward.

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In typical Martin fashion, the author had been dropping clues about the House Targaryen prequel project all along. “We have had five different Game of Thrones successor shows in development at HBO, and three of them are still moving forward nicely,” he wrote on his blog in May.

One of the three is the untitled prequel, written by Jane Goldman and starring Naomi Watts, which shot a pilot this summer. The project, now in post-production and awaiting word whether it will get a pickup, chronicles the world’s descent from the golden Age of Heroes into its darkest hour.

“Two other shows remain in the script stage, but are edging closer,” Martin wrote in May. “What are they about? I cannot say. But maybe some of you should pick up a copy of Fire & Blood and come up with your own theories.”

Coincidentally — or not — a large image of the Fire & Blood cover was featured just above this section in the same blog post with a note about the book’s success, having just re-entered New York Times’ Top 10 bestseller list where it had previously spent more than three months. “You can’t keep a good dragon down,” Martin wrote about the feat.

Named after House Targaryen’s words, Fire & Blood’s first volume was published last November with the tagline, “300 Years Before a Game of Thrones, Dragons Ruled Westeros.” The Targaryen history book, a companion to Martin’s A Song of Ice and Fire saga, goes back to a time when House Targaryen — the only family of dragonlords to survive the Doom of Valyria — took up residence on Dragonstone.

courtesy of HBO

Fire & Blood starts off with Aegon the Conqueror, creator of the Iron Throne, and goes on to recount the generations of Targaryens who fought to hold the throne, all the way up to the civil war, known as the Dance of the Dragons, that nearly tore their dynasty apart. The war will be a significant part of the TV adaptation, I hear.

Game of Thrones, which is based on A Song of Ice and Fire, featured a couple of surviving Targaryens, including Daenerys Targaryen (Emilia Clarke), Viserys Targaryen (Harry Lloyd), and Jon Snow (Kit Harington).

At TCA in July, HBO Programming President Casey Bloys would not comment on the status of the other GoT prequels besides the Watts pilot, but did not rule out the possibility for another GoT offshoot to get a green light by the end of the year. “It’s something I would not comment on,” he said.

D.B. Weiss and the cast and crew of “Game of Thrones” accept the award for outstanding drama series at the 70th Primetime Emmy Awards Shutterstock

Just days before, Game of Thrones had landed a whopping 32 Emmy nominations for its final season, breaking yet another Emmy record, for most nominations in a single year. The show, a three-time Outstanding Drama Series Emmy winner, also holds the Emmy record for most overall wins, 47 and counting, most wins in a single year, 12, and most total nominations for a scripted series, 161.

Beyond critical acclaim, GoT was a rare cultural juggernaut, with more than 45 million people tuning in for its final episodes.

“We are proud to have been the home for it, it’s been a great show for us,” Bloys said after the GoT finale in May.

A month earlier, Bob Greenblatt, chairman of WarnerMedia Entertainment and Direct-to-Consumer, addressed the possibility of putting multiple GoT- themed shows on the air in light of the original series’ enormous global success.

HBO

“It’s a double-edged sword,” he told Deadline. “We’re having conversations about how do we smartly continue the Game of Thrones universe, but we have to be really thoughtful about not killing the golden goose and not putting on shows that aren’t up to that quality level, and how many is too many.”

Bloys echoed his sentiment.

“I think Game of Thrones is a fantastic property but I don’t want to just be the home of prequels and sequels and all that stuff,” he said. “I think you want to be really careful about how you do it.”

Condal was the co-creator, executive producer and showrunner of sci-fi drama Colony, which aired on USA for three seasons. On the film side, he has been adapting Logan’s Run for Warner Bros. In addition to executive producing all GoT prequels, Martin executive produces the Wild Cards universe Hulu is developing based on his books. He also recently executive produced the Syfy series Nightflyers.

Condal and Martin have long-standing relationship. In 2016, Martin’s theatre in Santa Fe, Jean Cocteau Cinema, hosted a screening of Colony, followed by a conversation between Martin and Condal.

Condal is repped by Grandview and McKuin Frankel. Martin is with manager Vince Gerardis. Both Condal and Martin also were repped in the original deal for the project, which was made last fall, by WME.