Casting News: 'Game of Thrones' Prequel Adds 'Harry Potter' Actress Miranda Richardson

The cast of the upcoming Game of Thrones prequel just got even starrier with the addition of Harry Potter actress Miranda Richardson.

Two-time Oscar nominee Richardson, known for playing sneaky reporter Rita Skeeter in the Harry Potter movies, as well as roles in films such as Made in Dagenham and Belle, joins an awesome-looking ensemble cast led by Naomi Watts.

Other confirmed cast members for the prequel pilot include Denise Gough (Colette), Josh Whitehouse (Poldark), Toby Regbo (Fantastic Beasts: The Crimes of Grindelwald), Ivanno Jeremiah (Humans), Georgie Henley (the Chronicles of Narnia films), Naomi Ackie (Star Wars: Episode IX), Jamie Campbell Bower (the Twilight movies), Sheila Atim (Harlots), and Alex Sharp (Broadway’s The Curious Incident of the Dog in the Night-Time).

Richardson's role in the prequel hasn't yet been revealed, TVLine reports. However, we already know that Watts will be playing “a charismatic socialite hiding a dark secret.”

The official synopsis for the prequel teases: "Taking place thousands of years before the events of Game of Thrones, the series chronicles the world's descent from the golden Age of Heroes into its darkest hour. And 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."

Game of Thrones creator and author George R.R. Martin and Jane Goldman (Kingsman: The Secret Service) have collaborated on the story for the new series, which takes place thousands of years before what we saw go down in Westeros. Goldman will write the script and Martin will serve as an executive producer, and the prequel pilot is expected to air in 2010.

But of course, before we get too carried away with prequel talk, the eighth and final season of regular Game of Thrones is set to premiere April 21 on HBO, and it's bound to be dramatic.

Are you excited for the Game of Thrones prequel?