Updated: The “Game of Thrones” prequel pilot starring Naomi Watts is not going to series at HBO, Variety has confirmed with sources.

The cast and crew of the pilot were recently informed that HBO had passed on the project. The potential series was set to take place thousands of years prior to the events of the original series.

“After careful consideration, we have decided not to move forward to series with the Untitled Game of Thrones prequel,” HBO said in a statement. “We thank Jane Goldman, S.J. Clarkson, and the talented cast and crew for all of their hard work and dedication.”

In addition to Watts, the pilot starred Josh Whitehouse, Naomi Ackie, Denise Gough, Jamie Campbell Bower, Sheila Atim, Ivanno Jeremiah, Georgie Henley, Alex Sharp, Toby Regbo, Miranda Richardson, Marquis Rodriquez, John Simm, Richard McCabe, John Heffernan, and Dixie Egerickx.

Jane Goldman co-created the project with George R.R. Martin, whose “A Song of Ice and Fire” novel series served as the basis for “Game of Thrones.” Goldman and Martin wrote the story, with Goldman writing the teleplay. She would also have served as showrunner. She and Martin were executive producers along with SJ Clarkson, Daniel Zelman, James Farrell, Jim Danger Gray, and “Game of Thrones” executive producer Vince Gerardis. Chris Symes was co-executive producer. Clarkson also directed the pilot.

The pilot was one of several “Game of Thrones”-related projects that were put into development at HBO prior to the end of the series. At this time, none of the other projects are believed to be moving forward either.

However, it was reported in September that HBO was nearing a pilot commitment for a project based on based on the “Game of Thrones” companion book “Fire & Blood,” which tells stories of previous Targaryen kings like Aegon the Conqueror, the first ruler of Westeros, and Aegon the Dragonbane, all of whom are ancestors of Daenerys Targaryen (Emilia Clarke) and Jon Snow (Kit Harington).

The seventh and final season of “Game of Thrones” proved to be highly-divisive among fans, many of whom criticized the direction the show took in its final episodes. Nevertheless, “Game of Thrones” won 12 Emmy Awards for the final season, including best drama series. The season had been nominated for 32 Emmys in total, the most for any series in history in a single year.

Deadline first reported the pilot not going forward.

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