HBO is moving ahead with a Game of Thrones prequel, the first of five potential spin-off projects.
The company has given a pilot order for a prequel set thousands of years before the events of the Game of Thrones television show.
Depending on the quality of the pilot, the network will commission a full series.
Although untitled at the moment, the prequel was created by British screenwriter Jane Goldman alongside the author of the novel series, George RR Martin.
The series will chronicle “the world’s descent from the golden Age of Heroes into its darkest hour” according to HBO, and probe the secret histories of the warring families in a young Westeros.
It will cover a different period than George RR Martin’s new book, Fire and Blood, which is being released in November this year.
The book – which is an imaginary history, rather than a novel – is set 300 years before A Game of Thrones, “when dragons ruled Westeros”.
The eighth and final season of Game of Thrones is due to be broadcast in 2019.
Martin has said he is working with at least four other writers regarding further spin-offs, although details have not been released.
HBO and the author have discouraged fans from expecting these to feature the same characters as the Game of Thrones series.