Iconic blonde actress Naomi Watts's casting in HBO's upcoming Game of Thrones prequel as a socialite with a mysterious secret tempted us to jump to one very juicy conclusion: that she might be playing a Lannister, one of Cersei's ancestors, in the series. Considering the series is set before that other notable blonde family, the Targaryens, come to Westeros, it was a safe bet. Watts, who is currently in Northern Ireland filming the series, would know for sure. But we're just going to have to continue to guess.

However, a new interview with the GoT author George R.R. Martin (who created the prequel alongside Jane Goldman), as well as an accidental slip of what may or may not be some costuming from the show, seems to indicate that not only won't Watts be playing a proto-Cersei but no one will be playing a Lannister at all. Indeed, while some of the noble families we're already familiar with will be featured on the show (including the Starks), we could be introduced to dozens more.

“The Lannisters aren’t there yet, but Casterly Rock is certainly there; it’s like the Rock of Gibraltar,” Martin tells Entertainment Weekly in a new interview. “It’s actually occupied by the Casterlys—for whom it’s still named after in the time of Game of Thrones.” In the article, EW is quick to point out that the statement doesn't mean that the Lannisters won't show up at some point in the series.

"The Starks will definitely be there,” Martin also adds. “Obviously the White Walkers are here—or as they’re called in my books, the Others—and that will be an aspect of it…There are things like direwolves and mammoths.”

Notably, there's no word on dragons. There'll certainly be a whole lot of people, though. The announced cast is already extensive, but Martin adds that while Westeros had been divided into seven kingdoms for quite some time in the original series, during this one there'll be something like 100 kingdoms.

We don't know which of those houses Watts's character will hail from, but some fans think she may have revealed her character's hair color.

Watts, like most of us, has currently come down with a case of Big Little Lies fever. The fact that she's been best friends with Nicole Kidman for decades (and maintains friendships with other members of the cast, including Laura Dern), doesn't get in the way of her fandom either. While sitting in her GoT prequel makeup chair recently, Watts snapped a photo of herself watching the latest episode on her laptop. Eagle-eyed fans, however, zeroed in on what seems to be a brunette wig in the background.

See it there? The clump of hair over her shoulder, beside the can of hairspray? You really can't make out much of it, aside from the shade of brown, and there's no telling if the wig is actually meant for Watts (though it clearly looks like she will be doing some wig work for the show instead of using her real hair), or someone else. But it would jibe with the fact that Watts is playing someone from a non-towheaded family.

Whatever the case, Watts may be prominent in the new series, but Martin doesn't call her the lead. Indeed, he tells EW that his show may be even more of a ensemble show than its predecessor.

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