Sophie Turner was left in shock after her “X-Men: Dark Phoenix” co-star Jessica Chastain dropped some major “Game of Thrones” Easter Egg knowledge on her.

[SPOILER ALERT: The remainder of this article will discuss the series finale of “Game of Thrones.”]

HBO’s popular fantasy drama ended on a controversial note with fans after crowning Brandon Stark as the king of the six kingdoms. The move came after Turner’s character, Sansa Stark, declared the North independent and eventually crowned herself Queen on the North.

'PAWN STARS' RICK HARRISON APPRAISES RARE 'GAME OF THRONES' BOOK, SAYS AMERICANS AREN'T LEARNING FROM HISTORY

Speaking with Metro to promote the new “X-Men” film, Turner and Chastain couldn’t help but talk about the popular series. Things started when the interviewer asked the 23-year-old Sansa actress if there was any foreshadowing about her character’s ultimate fate throughout the series.

“I don’t know, I haven’t really looked back far enough,” Turner said. “Well, the first episode of Season 1, Sansa goes, ‘I want to be queen, mummy, someday.'”

EMILIA CLARKE SPEAKS OUT ABOUT 'GAME OF THRONES' FINALE: 'I STAND BY DAENERYS'

That’s when Chastain revealed her intimate knowledge of the show dating back to some Season 1 promotional material.

“You know the poster for the first season — you know what’s on it?” Chastain, 42, asked Turner. “So it’s your papa on the throne, and there’s a raven on the throne, right to his right.”

The realization appeared to hit Turner like a ton of bricks, but she was wary about talking further as she still doesn’t want to spoil the show’s ending for those that haven’t seen it.

“We can’t talk about it,” she whispered through cupped hands.

CLICK HERE TO GET THE FOX NEWS APP

The poster in question sees Sansa’s father, Ned Stark, sitting on the iron throne with a raven by his side. As fans know, Brandon went off beyond the wall for most of the series to become the enigmatic Three-Eyed Raven. Chastain seems to be pointing out that the raven by his father’s side implies that Brandon was destined for leadership all along.