Melisandre always warned everyone that the night was dark and full of terrors in Game of Thrones – and Sunday night's episode proved just how right she was.

"The Long Night"—the third episode in GoT's Season 8—brought the Night King's army of the undead down upon the Northern forces and Daenerys Targaryen's army. Before the battle began, though, a woman in a dark cloak—The Red Priestess herself —arrived at Winterfell. And Melisandre, played by actress Carice van Houten, was instrumental in helping the gang achieve victory.

When Melisandre arrived at Winterfell at the start of "The Long Night," she was met with uneasy looks—not just from Davos Seaworth (Liam Cunningham), who was ready to kill her for what she did to Shireen Baratheon seasons ago—but from Ser Jorah Mormont (Iain Glen). Melisandre's brief interaction with Jorah, where she had him translate "lift up your swords" so she could light up the Dothraki arakhs, was van Houten's first spoken scene with Glen. The episode provided her first onscreen interactions with other longtime cast members, too.

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Image via HBO

"Yes, that was great. When you see the show over the years, you become a fan yourself. How can you not?" the actress told Collider. "And then to work with them, I sort of got almost a bit starstruck. It's funny because most of them I didn't really see [while filming over the years]. Not even at premieres. Sometimes we missed each other. So all of sudden it's like, 'Ah! I'm having a scene with Ser Jorah!'"

Lighting the arakhs came easy, but as the battle waged on, a retreat was called and Winterfell needed the trench outside the castle walls lit for protection. When Davos couldn't signal Dany or Jon Snow with his torches, the task of setting it alight fell to Melisandre (with an assist from an Unsullied protection guard, led by Grey Worm). In that moment, as she was just a few feet away from the attacking undead, fear – and even doubt (which has plagued her since the Shireen incident) – washed across Melisandre's face as she tried to concentrate and use her spell to eventually light it up.

"I did feel a responsibility to sort of show in this very short moment how high the stakes were … for everyone," she explained when asked about the difficulties of playing all of the emotions we saw in that scene. "So I'm happy that you actually see that bit of doubt because yes, she has been wrong before and yes, she brought Jon Snow back to life, but that sort of surprised her as well. And she has to play it cool in order to make it work, but I think underneath it -- I mean, she's literally four feet away from the zombies while trying to light this trench. But of course, it's great that you can see a bit of doubt and fear there."

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Image via HBO

And while the trench couldn't keep the undead out of Winterfell for long, Melisandre had another hand to play. She delivered the right words at the right time, inspiring Arya Stark (Maisie Williams) to go and kill the blue-eyed Night King.

"It was great," van Houten said of her reaction to learning about that Melisandre/Arya moment. "I was happy that I finally sort of really did something good, like obviously good … inspiring and positive. And also, it had that sort of girl power moment — that moment like, 'Go get 'em, girl!' — almost a motherly quality and that's where I guess her sort of — her age comes out a bit."

Ah yes, Melisandre's age. With death defeated, Melisandre removed her necklace, returned to her true age and died in the snow.

"Already on the paper, it was quite touching, I thought. I got goosebumps when I read it," van Houten said when Collider asked for her reaction to finding out Melisandre would be the last shot in "The Long Night," with her character's work done.

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Image via HBO

"I felt like that whole episode was like a symphony, like a classical piece of music that sort of has buildups and big, bombastic parts. And then, in the end, there's just that cello and the piano and it was such a beautiful ending anyway, apart from the fact that it was me. If it would've been anyone else, it would have been great too. So, it was just that buildup and that die down. … It was just like a trip," she added.

Melisandre's final scene – and her transition to old age – was watched in shock, anger, and confusion by her GoT series foe – Davos Seaworth, who was still ready to avenge Shireen when dawn came following the battle. Van Houten and Cunningham starred in 2011's Black Butterflies and were paired together in Thrones, beginning in 2012's Season 2, and she will miss working with him on the show.

"I'm definitely going to miss that. … He was one of the first people that sent me a message actually, after the show aired and he said, 'Great performance. Sorry I didn't get to kill you,'" she shared.

Van Houten responded to Cunningham's text with a chuckle.

"I just laughed. I just thought it was so typical for him to write that. I couldn't have been more lucky with him as a co-actor all those years," she added.

Arya killing the Night King
Image via HBO
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Image via HBO
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