In true 'Game of Thrones' fashion, only three out of the five spin-offs announced some time ago still survive according to George RR Martin.

Via his official blog, Martin teased the surviving shows and even got an utterly obvious plug for 'Fire & Blood', his most recent book. "The one I am not supposed to call ‘The Long Night’ will be shooting later this year, and two other shows remain in the script stage, but are edging closer," explained Martin.

"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."

Well, as fate would have it, we actually have a copy of 'Fire & Blood' on hand. The novel, which is basically written like a history book, takes place 300 years before the events laid out in 'Game of Thrones' and the novel series.

The book follows the history of the Targaryen conquest of Westeros, beginning at the Doom of Valyria and following the conquest of Aegon I Targayen, also known as Aegon the Conqueror. All told, it covers the first 150 years of Targayen rule in Westeros, so it's definitely ripe in terms of plot and the characters spoken of in it could easily be adapted for screen.

One of the spin-offs that Martin refers that definitely isn't called 'The Long Night' is set way, way, WAY in the past, during the Age of Heroes where the descendants of the Starks helped to build the Wall that kept the White Walkers out and cut off Westeros from the icy tundras beyond.

That series has already cast Naomi Watts, 'The Rise of Skywalker' star Naomi Ackie, 'Doctor Who' alum John Simm, and Irish actor Denise Gough and is set to begin production in the coming months.

As Martin points out, none of these are anywhere near sold to HBO and the studio have been open about the fact that if none of these shows live up to 'Game of Thrones', they won't be put through to series.