It will chronicle the world's descent from the golden age of heroes to its darkest hour, according to HBO.
The show in question comes from Jane Goldman and George R.R. Martin himself, and is going way back, before Robert's Rebellion, before Dunk & Egg, before The Dance of the Dragons, Aegon's Conquest, and even the Doom of Valyria.
In the Thrones universe, "the Long Night" refers to an epoch in which night lasted a generation, Westeros was decimated and the White Walkers rose to power. "More likely HBO will want to work the phrase "game of thrones" in there somewhere". In the midst of this cold climate, the White Walkers soon descended upon Westoros from the north and engaged in a long war in an attempt to cover the world in an interminable winter. She and Martin will executive produce along with Daniel Zelman and Game of Thrones executive producer Vince Gerardis.
Last week, HBO ordered the first (of many?) Game of Thrones prequel pilot.
There's no director, cast, location or title yet, Martin says - but he does have a title idea. "The Long Night lasted a generation and laid waste through starvation and terror".
As for the other successor shows... if you have been following along, you know that we started with four, and eventually went to five. If I wasn't busy with Winds, don't you think I'd be scripting one or more of these pilots myself?
On his personal site, Martin discussed HBO giving the green light to Jane Goldman's series, noting that no characters from Game of Thrones will appear, as it's set tens of thousands of hears before the main series. "But this is television, so nothing is certain". Or, well, it would be if George R.R. Martin had his say.