"And you know the poster for the first season, do you know what's on it?" Chastain asked Turner while discussing foreshadowing in the show. "So it's your papa on the throne and there's a raven on the throne."
That's when Turner's mouth fell open and her eyes went wide. She quickly put her finger to her lips, looked around and whispered, "We can't talk about it." It seems someone in her entourage hasn't quite made it to the end of the show.
The raven sitting on the Iron Throne is significant because, during Bran's journey throughout the show, he heads far north beyond the wall where he encounters an old man called the Three-Eyed Raven who, it turns out, is the keeper of the memory of man. Eventually, Bran himself is bestowed with this role, making him exceedingly important and, for a time, a target of the Night King.
It hasn't been clarified if the raven is intentional on the part of the show's creators or was simply an aesthetic choice for the poster. Regardless, the discovery has fueled heated debate.
As for Sansa's fate, Turner has made it clear that she is more than satisfied with how she ended up on the show -- ruling as Queen in the North.
"I love the way that Sansa's journey ended," she recently told ET. "I think it was kind of the one thing that she wanted throughout the whole show…to be home and to be where she felt most safe and comfortable and that's Winterfell. She's totally capable of leading those people."
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The 23-year-old actress went on to explain that, early on in the show, her character got over the idea of becoming the queen of Westeros.
"Since she got to King's Landing in season one, she never wanted that Iron Throne," she continued with ET. "She never wanted to rule over that many people… I think, watching how this character finished on Game of Thrones was the most satisfying ending."
"I agree with that," Chastain chimed in, later commenting, "Queen of the North. That's better… There's no Iron Throne anymore, first of all… But yeah, absolutely, I'd said that to her. I said it was my favorite, her and Arya, are my favorite arcs of the series."