'Game of Thrones' Cast Rocks the Red Carpet for Final Season Premiere

Warning: Spoilers ahead!

Arya Stark had her first sex scene during Sunday night's "Game of Thrones" and Maisie Williams, who plays the character, was just as shocked when she read the script as viewers were while watching it.

On the latest episode of the HBO fantasy drama, we saw Jon Snow (Kit Harington), Daenerys Targaryen (Emilia Clarke), Tyrion Lannister (Peter Dinklage) and Co. prepare for the upcoming battle against the Night King and his army. While some people, like Tyrion, chose to get drunk on what might be their last night in the world, Arya decided she didn't want to die a virgin and turned to her handsome friend Gendry Baratheon (Joe Dempsie) for help.

In an interview with EW, Williams recalled her reaction when she first read the script. According to the 22-year-old actress, she thought the entire scene was a joke.

"At first, I thought it was a prank," Williams said. "I was like, 'Yo, good one.' And [the showrunners were] like, 'No, we haven't done that this year.' Oh f--k!"

Williams' bestie, Sophie Turner, who plays Sansa Stark on the series, was the first to break the news to Williams.

"I called Maisie and was like: 'Have you read it yet?'" Turner recalled to the publication. "And she's like, 'I'm midway through episode one.' And I'm like: This scene, this page, read it! This is awesome! She was very happy."

Williams added, "Sophie said, 'Whatever you do, you have to skip to this episode, this scene first.' So I just read that and it was practically all I knew about the entire season."

"I got to the read-through," she later recalled. "I'm reading the scene and thought, 'Oh, we're actually going to do this. When do I shoot this? I need to go to the gym.' A whole list of things."

Williams, who was only 11 when the series began, has (literally) grown up before our eyes throughout the show's seven seasons. The British actress said the showrunners, David Benioff and Dan Weiss, let her make the decision about how much she wanted to show during the scene.

"David and Dan were like: 'You can show as much or as little as you want,'" Williams said. "So I kept myself pretty private. I don't think it's important for Arya to flash. This beat isn't really about that. And everybody else has already done it on the show, so..."

"Then [the scene] was rushed," she continued. "We were [directed by] David Nutter, who has a habit of speaking fast anyway. By the end we're rushing to finish the scene and David is going, 'Okay, you're going to come in and do this and do that and, great, take your top off' -- and then walked off. And I'm like... 'Okay. Let's do it.'"

After the scene aired, many fans googled Williams' age and how old Arya is supposed to be (18) as they were concerned the character was too young to be having sexual relations with Gendry. Dempsie, 31, said it was a little awkward for him because he's known Williams since she was 11.

"It's obviously slightly strange for me because I've known Maisie since she was 11, 12 years old," he said. "At the same time, I don't want to be patronizing toward Maisie -- she's a 20-year-old woman. So we just had a lot of fun with it."

For Williams and fans alike, it was nice to see Arya do something normal rather than her adventures as a Faceless Man assassin and being "laser-focused" on staying alive.

"It was really interesting because it's a very human relationship for Arya," Williams explained. "This is something she's stayed away from, an emotion we've never really seen her engage with. David and Dan were like, 'It's the end of the world, what else would you have her do?' This may be is a moment where Arya accepts death tomorrow, which she never does -- 'Not Today.' So it was that moment where she says, 'We're probably going to die tomorrow, I want to know what this feels like before that happens.' It's interesting to see Arya be a bit more human, speak more normally about things people are scared of."

"Game of Thrones" airs Sunday nights at 9 p.m. EST on HBO.

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