The new "Game of Thrones" prequel is about to be greenlit by HBO. According to Deadline's exclusive report, the network is close to ordering a pilot for the second "Game of Thrones" prequel co-created by George R. R. Martin and Ryan Condal, the executive producer of "Colony." The series will be taking place roughly 300 years before the events of the main series and will track the beginning of the end of the House Targaryen rule over Westeros. HBO is still silent on the matter.

The show is based on 'Fire & Blood'

The prequel, co-created by "A Song of Ice and Fire" author George R.

R. Martin and "Colony" executive producer Ryan Condal, has been in development since the fall of 2018. According to the report, the show is based on the first volume of Martin's "Fire & Blood" that was released in November last year. The book follows the first part of the Targaryen rule in Westeros, from Aegon's conquest to the aftermath of the Targaryen civil war a.k.a. The Dance of the Dragons.

Sources say that this project isn't a sixth "Game of Thrones" prequel. Instead, it's a new take on one of the five prequel scripts that the network commissioned back in 2017. The script in question is the one by former "Game of Thrones" writer and co-executive producer Bryan Cogman who confirmed earlier this year that his spinoff isn't happening.

George R. R. Martin on 'Game of Thrones' prequels

George R. R. Martin has been teasing the prequel about the Targaryen rule in Westeros for a while now. In May, the "A Song of Ice and Fire" author wrote on his blog that three of five "GoT" successor shows "are moving forward nicely." He added that the other two projects are in the script stage, but are edging closer.

Martin didn't want to reveal what these shows will be about. He did, however, urged his readers to pick up a copy of his latest book "Fire & Blood" and come up with theories.

One of these projects is the yet-untitled "Game of Thrones" prequel set thousands of years before the main series during the Age of Heroes. The show will chronicle the world's descent from this golden age of Westerosi history into its darkest hour, the period known as the Long Night when the White Walkers first invaded.

The pilot for this series co-created by Martin and Jane Goldman has already been shot and is now waiting for HBO's approval.

Deadline's exclusive report also says that the Targaryen civil war (the Dance of the Dragons) will be a major part of the upcoming prequel. "Game of Thrones" fans have every reason to be excited given the fact that this is one of the most exciting periods in recent Westerosi history full of political intrigue, and yes, dragons, lots and lots of dragons.