Get ready to return to the world of Westeros, as HBO has started filming their Game of Thrones Prequel series. Work began on this show long before the flagship series ended its run earlier this year. The premium cable network knew they wanted to keep this money train moving, but with creators David Benioff and D.B. Weiss wrapping up their story with season 8 on the main show, they had to turn elsewhere. While many details remain mysterious, cameras are rolling on the new series.

According to multiple reports, production has, rather quietly, kicked off on the untitled new show. Creator George R.R. Martin previously suggested the series was perhaps going to be called The Long Night, but that has since been shot down. Filming is taking place in Northern Ireland, which is a familiar location for Game of Thrones. All eight seasons of the hit fantasy series filmed near where the prequel is being shot as we speak. It's unclear if HBO will try and set up shop for the series there in the long run, or if they will be filming in other countries as things progress.

One might wonder why HBO didn't make some sort of splashy announcement regarding the start of production. There are a couple of reasons for that. For one, Game of Thrones season 8, especially the finale, left a lot of viewers feeling cold. As such, they may want to avoid releasing any Westeros related news for a while. It was also recently revealed by HBO Programming President Casey Bloys that they are first shooting a pilot for this new show, then will decide whether or not they order it to series. So they may not want to make a formal announcement regarding the show until they know for sure it's going to make it to air.

This new series will take place thousands of years prior to the events depicted in the main series. No dragons. No Iron Throne. The cast for the new show will be led by Oscar-nominee Naomi Watts. Naomi Ackie (Star Wars: The Rise of Skywalker), Josh Whitehouse (Northern Soul), Denise Gough (People, Places and Things), Jamie Campbell Bower (The Mortal Instruments: City of Bones), Sheila Atim (Girl From the North Country), Ivanno Jeremiah (Doctor Who), Georgie Henley (The Spanish Princess), Alex Sharp (How To Talk To Girls At Parties) and Toby Regbo (Fantastic Beasts: The Crimes of Grindelwald) round out the ensemble.

This is just one of several possible spin-offs that HBO is developing. Jane Goldman developed the new series alongside George R.R. Martin. Goldman will also serve as showrunner. S.J. Clarkson (Jessica Jones) is set to direct the pilot. It isn't yet clear when exactly the series will make it to air, should HBO decided to pick it up for a full season, but the expectation is that it would be ready to go by late 2020. We'll be sure to keep you posted as any further details on the show are made available. This news was previously reported by Entertainment Weekly.