With the final season of Game of Thrones premiering on HBO next month, fans are eager to learn more about the upcoming prequel series.

According to Entertainment Weekly, Harry Potter alum Miranda Richardson has been added to the prequel’s cast. Richardson is widely known for her role as Rita Skeeter in the Potter films, and has also had roles in Sleepy Hollow and The Hours. No additional details have been released about her character.

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Richardson joins previously announced cast members Naomi Watts, Josh Whitehouse, Georgie Henley, Naomi Ackie, Denise Gough, Jamie Campbell Bower, Toby Regbo, Sheila Atim, Ivanno Jeremiah and Alex Sharp.

The prequel will premiere after the conclusion of Game of Thrones, likely in 2020 or later. It 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."

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Season 8 of Game of Thrones, the show’s final season, will premiere April 14. It will feature six episodes with longer than usual runtimes. The HBO drama stars Peter Dinklage as Tyrion Lannister, Nikolaj Coster-Waldau as Jaime Lannister, Lena Headey as Cersei Lannister, Emilia Clarke as Daenerys Targaryen, Sophie Turner as Sansa Stark, Maisie Williams as Arya Stark and Kit Harington as Jon Snow.