Maisie Williams arrived at the table read for the final season of Game of Thrones not yet realizing that Arya Stark kills the Night King.

Like her co-star Kit Harington (Jon Snow), she hadn’t read the season 8 scripts (well she had read some parts) and instead wanted to largely experience the final season performed live by her castmates around a conference room table in Belfast.

“I was coming into work and everybody was talking about episode 3 and [director Miguel Sapochnik] was like, ‘Have you read the [season 3 script] yet?’” she recalls.

When GoT star said she had not yet read the episode, Sapochnik replied, “Oh, I can’t tell you then.”

Williams couldn’t understand his reluctance. “I was like, ‘Are we fighting the wights? Does The Night King die? So who kills him? What happens?’ And no one would say anything. Why is no one saying it? This is crazy.”

When the cast reached the end of episode 3 where Arya saves the Seven Kingdoms by sprinting into the action and stabbing the Night King with her Valyrian steel dagger, “it got a huge f—king cheer,” Harington recalls.

The twist is a monumental success for her character, and entirely unexpected. It was so unexpected, however, Williams initially worried fans wouldn’t like it.

“It was so unbelievably exciting,” she says. “But I immediately thought that everybody would hate it; that Arya doesn’t deserve it. The hardest thing is in any series is when you build up a villain that’s so impossible to defeat and then you defeat them. It has to be intelligently done because otherwise people are like, ‘Well, [the villain] couldn’t have been that bad when some 100-pound girl comes in and stabs him.’ You gotta make it cool. And then I told my boyfriend and he was like, ‘Mmm, should be Jon though really, shouldn’t it?’”

Yet Williams came around to embracing the idea as the team began to film the episode, particularly after shooting the scene where Melisandre (Carice van Houten) gives Arya a pep talk and reminds her of the Red Woman’s “brown eyes, blue eyes, green eyes… eyes you’ll shut forever” prophecy from season 3 — trying to stop the Night King is Arya’s destiny.

“When we did the whole bit with Melisandre, I realized the whole scene with [the Red Woman] brings it back to everything I’ve been working for over these past 6 seasons — 4 if you think about it since [Arya] got to the House of Black and White,” Williams says. “It all comes down to this one very moment. It’s also unexpected and that’s what this show does. So then I was like, ‘F—k you Jon, I get it.’”

Harington says he was also shocked that Arya got to be the one to finish off the Army of the Dead leader, particularly after the famous come-at-me-bro Jon vs. Night King face-off in “Hardhome,” yet he appreciated the dramatic reversal.

“I was surprised, I thought it was gonna be me!” Harington says. “But I like it. It gives Arya’s training a purpose to have an end goal. It’s much better how she does it the way she does it. I think it will frustrate some in the audience that Jon’s hunting the Night King and you’re expecting this epic fight and it never happens — that’s kind of Thrones. But it’s the right thing for the characters. There’s also something about it not being the person you expect. The young lady sticks it to the man.”

For Miguel Sapochnik, the director’s goal was to get fans utterly convinced Jon was going to kill the Night King, and then pull out the rug. “I thought, ‘Hmm, if I see Arya running then I know she’s going to do something.’” Sapochnik says. “So it’s about almost losing her from the story and then have her come in as a surprise and pinning all our hopes on Jon being the guy going to do it — because Jon’s always the guy. So we follow Jon in a continuous shot I want the audience to think: ‘Jon’s gonna do it, Jon’s gonna do it…’ and then he fails. He fails at the very last minute. So I’m hoping that’s a nice switch that no one sees coming. “

Williams was one of a couple dozen actors and hundreds of crew members who had to endure the Battle of Winterfell’s infamous 55 nights of shooting during amid freezing Northern Ireland rain, an effort that which EW detailed in its recent cover story.

“I’ve never been in a battle before,” Williams said. “Arya’s never in it. Episode 9, I skip every year. Which is bizarre since Arya’s the one that’s been training the most. I’ve never been around that way of working. I feel like I’ve always been part of this big show but in terms of being part of the episodes that really define us, this is my first taste of it. And I’ve been thrown in the deep end, as well … You try and you train but nothing can prepare you for how physically draining it is. It’s night after night and again and again and it just doesn’t stop. And you can’t get sick — you have to look out for yourself because there’s so you have to do that nobody else is going to … But the sense of achievement after a day on set is unlike anything else. One of those really tough days, you know it’s going to be part of something so iconic and it will look amazing.”

Read more “The Long Night” coverage:
— Melisandre actress Carice van Houten on the Red Woman’s final sacrifice
— Lyanna Mormont actress Bella Ramsey discusses her Winterfell battle fate
— Game of Thrones releases trailer for season 8’s mysterious episode 4
— Our deep-dive recap for “The Long Night”

More “The Long Night” coverage to come Monday and Tuesday…