With the final season of HBO's Game of Thrones rapidly approaching, complete with what's been described as six movie-like episodes to wrap up the story, the premium cable giant isn't standing still. HBO is already moving forward on its prequel series, which will premiere sometime after the core shows finishes up, likely 2020 or later. Joining Naomi Watts and Josh Witehouse, HBO has now announced eight more actors being added as series regulars.

The lucky eight are not household names, but you've likely seen most of them before. The Chronicles of Narnia fans will know Georgie Henley better as Lucy Pevensie. Naomi Ackie has appeared on Doctor Who and will be popping up in Star Wars: Episode IX. Denise Gough voiced Yennefer in The Witcher 3 and was in a couple episodes of the Netflix serial killer drama The Fall.

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Jamie Campbell Bower, who played a young King Arthur for Starz in Camelot, is joined by fellow Harry Potter franchise alum Toby Regbo. Bower and Regbo are probably best knows as Young Grindelwald and Young Dumbledore, respectively. Additionally, Harlots' Sheila Atim, actor Ivanno Jeremiah (Humans, Black Mirror) and Alex Sharp (How to Talk to Girls at Parties) are on board as well. Details about the characters are still unknown, but there is a lot of genre credit between them.

The prequel series will be set thousands of years before the events of the current show, and according to HBO, "Only one thing is for sure: From the horrifying secrets of Westeros' history to the true origin of the White Walkers, the mysteries of the East to the Starks of legend — it's not the story we think we know."

The pilot comes from showrunner Jane Goldman and franchise creator George R. R. Martin. Additionally, director SJ Clarkson (Jessica Jones, Star Trek 4) has been hired to helm the first episode.

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(via The Hollywood Reporter)