George RR Martin updates fans on Game of Thrones spin-offs – and says we shouldn't call them 'spin-offs'

Writing on his blog, Martin explained that three out of the five Game of Thrones "successor shows" (his preferred term) were still progressing well.

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"We have had five different Game of Thrones successor shows in development (I mislike the term 'spin-offs') at HBO, and three of them are still moving forward nicely," he wrote.

"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," he added.

Martin had previously appeared to reveal that The Long Night would be the title of the first official prequel series, before later walking back on his comments. However, clearly the author is still keen on recycling the title used for season eight episode three's Battle of Winterfell.

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According to HBO, the first prequel series will be set around 5,000 years before the events of the main drama during a time known by Game of Thrones characters as the Age of Heroes, a period of history when iconic and near-mythical figures had all sorts of unusual adventures.

Martin has previously hinted that all of the series currently being worked on are expected to be prequel series. The other shows are still shrouded in mystery, but the author did hint that a little trip back through Game of Thrones folklore might help fans figure them out.

"What are they about? I cannot say. But maybe some of you should pick up a copy of [Targaryen history book] Fire & Blood and come up with your own theories."

Game of Thrones continues Mondays at 2am and 9pm on Sky Atlantic