HBO has cancelled the Game of Thrones prequel TV series that was tentatively known as The Long Night. The show's pilot episode began filming last July in Northern Ireland, with Naomi Watts (in an unknown role) leading the cast and S.J. Clarkson directing from a screenplay by showrunner Jane Goldman (Kick-Ass, Kingsman). It was one of a handful of Game of Thrones prequel series put into development by HBO, ultimately becoming the first of them to make it to production.

The first real signs of trouble for The Long Night came in September, when HBO started moving forward with a separate Game of Thrones prequel about the history of House Targaryen, this time created by A Song of Ice and Fire author George R.R. Martin and Ryan Condal (Colony). Given the absence of updates on the Goldman-Clarkson pilot episode since then, rumors began to circulate that the show was in danger of being scrapped altogether. Turns out, there was fire behind that smoke after all.

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According to Deadline, The Long Night Game of Thrones prequel is no longer moving forward at HBO. The network has yet to officially confirm the news, but Goldman has (reportedly) already begun to email the pilot's cast and crew, telling them the project is dead.

Richard Brake as the Night King on Game of Thrones

The Long Night picked up thousands of years prior to the events of Game of Thrones and and (according to HBO's plot summary) would've explored "the true origin of the white walkers [and] the mysteries of the East", among other legends about the history of Westeros and Essos. By comparison, the as-yet untitled prequel being developed by Martin and Condal is set 300 years before the story in Game of Thrones, and reveals the beginning of the end for House Targaryen, paving the way for their eventual descendant, Daenerys Targaryen, to start her own campaign of blood and fire to reclaim the Iron Throne. There aren't too many details about why The Long Night was cancelled just yet, but Deadline's report cites troubles in post-production and problems with filming in Northern Ireland as possible culprits.

Of the pair, Martin and Condal's show is more directly connected to the narrative in Game of Thrones and, as such, sounds like the more conventional prequel series on paper. It's plausible that, in addition to the issues mentioned, HBO feels a more straightforward prequel co-created by Martin is the safer bet at the moment, especially coming on the heels of Game of Thrones' widely-seen, but heavily criticized final season and the subsequent criticisms levied at showrunners David Benioff and D.B. Weiss for their recent comments about the series and their time working on it. Whether that's the right call, of course, only time will tell.

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We will bring you more Game of Thrones-related updates as they become available.

Source: Deadline