One of the highly anticipated Game of Thrones prequels has just found its leading lady!

Deadline reports that Naomi Watts has been cast in prequel series detailing the world of Westeros thousands of years before the time of Jon Snow (Kit Harington) and Daenerys Targaryen (Emilia Clarke). Details on her character are unsurprisingly sparse — we don't even know this woman's name yet — but we do know Watts will be playing a charismatic socialite hiding a dark secret.

Just because this series is set millennia before Game of Thrones, that doesn't mean we won't be getting our fair share of Westerosi history. In fact, the series description hints that we'll actually be diving deeper into several of the mysteries Game of Thrones has never fully explained: "It 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."

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This unnamed prequel series has no expected premiere date or other cast members attached.

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Peter Dinklage and Emilia Clarke, <em>Game of Thrones</em>Peter Dinklage and Emilia Clarke, Game of Thrones