SPOILER ALERT: Do not read on if you have yet to see the season four finale of "Game of Thrones," titled "The Children."

The season four finale of "Game of Thrones" may not have beaten the body count of the Red Wedding, but the hour still boasted a number of shocking deaths (unless you're a "Song of Ice and Fire" reader) and epic battles, including Stannis Baratheon's (Stephen Dillane) raid against Mance Rayder's (Ciarán Hinds) wildling army, and Bran Stark's (Isaac Hempstead Wright) harrowing encounter with the wights during his quest to meet the three-eyed raven.

Among the major casualties of the season closer: Tywin Lannister (Charles Dance), prostitute Shae (Sibel Kekilli) and Jojen Reed (Thomas Brodie-Sangster), with Sandor "The Hound" Clegane (Rory McCann) left for dead by Arya Stark (Maisie Williams) after a brutal confrontation with Brienne of Tarth (Gwendoline Christie).

Variety talked to Kekilli and episode director Alex Graves about the epic scope of "The Children," including the difficulty they both faced in filming Tywin and Shae's brutal death scenes following Tyrion's (Peter Dinklage) escape from the Red Keep, and the most intimidating scene Graves had to tackle: Bran and company's confrontation with the wights.

"One of the brilliant moves that David [Benioff] and Dan [Weiss] did … is they pulled this crescendo in Brandon Stark's story up and put it into this episode. In other words, they almost jumped forward a year in what happens to Bran, because let's face it, we're tired of him being carried across the continent by Hodor," Graves laughed. "When I read the outline, I called David and Dan, I went straight to Hollywood and met them and I said, 'Are we talking about the zombie guys that we've been doing or could these guys be viciously dangerous?' They said, 'Oh, yeah, that would be great.' So they go across this snow plain and skeletons start to come out of the snow, à la Ray Harryhausen, who we sort of privately dedicated the sequence to. They come out of the snow at 90 miles per hour, and they are there to kill Brandon and Jojen before they get there, and they've been waiting for like a thousand years. Nobody knew about the sequence and it [wasn't] in any of the marketing, which is the most brilliant marketing move I've seen."

"The logistics were that it was far too complex to shoot in Iceland in six hours of daylight and ten below weather. So we had a couple meetings about it, and I was really worried about needing to film it where the backgrounds were neutral in case whatever we did with skeletons needed to be manipulated dramatically with green screen," he continued. "Chris Newman, who is one of the great producers on the show, had found this French film where they created these skeletons using guys with a certain technical approach. It was a poor man's motion control but it worked really well. We needed to do something like that, because it was such a fast-paced action sequence ... I storyboarded that sequence on napkins at a restaurant on my third day on the job, because we had to get going on it. To tell you the truth, we started working on it last May, and they finished it about two weeks ago. So it was a combination of, we've got to shoot at night; we have to create a gigantic set of ice plain in a rock quarry in Northern Ireland; we're going to have stuntmen who are almost anorexic, wearing skeletal costumes over green leotards; choreograph the shots -- we actually pre-shot it on my little camera and cut it together. That was when we started to get excited and when we started to go, 'Yeah, we can do this.' It was very complicated."

Graves admitted that his "secret favorite scene -- which I have to say I was obsessed with -- was Brienne finding Arya and The Hound" and their ensuing battle over who was worthy of watching over the youngest Stark daughter -- even though it ended with The Hound's (assumed) demise. "The writing of the train-wreck that that sequence is, is so brilliant, that I was just so in love with it," he laughed.

The segment with Stannis raiding the North and coming to the aid of the Night's Watch, meanwhile, was the most challenging financially, according to Graves -- which may explain the truncated confrontation that saw Stannis' forces confront Mance Rayder's army North of The Wall, instead of during the Battle of Castle Black as it was depicted in George R. R. Martin's "A Storm of Swords."

"Game of Thrones" is undoubtedly the most ambitious series on television in terms of scope, shooting on multiple continents across multiple episodes simultaneously, and Graves admitted that he worked on all four of his episodes at once, after reading all ten installments of the season in order to understand the overarching plotlines that were woven throughout.

"The thing about it that's fun is that I'm directing episode 2 when Joffrey dies, but I'm really thinking about the finale and how it's heading towards that," he explained. "When I'm doing Ramsay killing his girlfriend with dogs, I know that I'm setting up a childish homicidal maniac who will inherit the North at the end of the season. You know these things, and especially with Cersei and Tyrion, you are so well-served by knowing where they begin and end, and it's much more like doing a play than doing a TV show, because you really understand the arcs and can pick up much more detail. It's a big part of why the show is so good -- you can tell when you watch that everyone knows what they're doing."

While keeping track of storylines may seem complicated on paper, Graves insisted that "the wrangling of everything is very easy because the producers are so incredibly helpful and smart and work so hard, that you really are riding their rocket in some ways. They come in with, 'What do you want to do?' and they get you going, and then they really work night and day to make it happen in a way that's affordable and makes sense ... Really the entire focus in directing the show is, 'Am I really telling the story of the ten-hour movie as effectively as I can?' The other thing was, I would say to Emilia [Clarke] or somebody, 'Okay, that's how we expect the scene to go, so now let's keep going.' And they get it. A scene that, even if you've read the books, even if you've read the scripts, [you try to make it] even more interesting. You're always looking for that other angle and Emilia's somebody -- and Kit Harington this season -- is incredible at adding that third layer of the emotional journey of the character that you wouldn't have thought was there, that pulls you in even further."

As "Game of Thrones" fans well know, the Lannisters always pay their debts, so it was no surprise that before the finale came to a close, Tyrion finally got his revenge on former lover Shae and his sadistic father Tywin, who -- in the ultimate act of betrayal -- ended up in bed together following Tyrion's trial.

Graves said that those deaths were the "most exhausting" for him to shoot, because he felt "such intense pressure to make sure that Peter and Sibel and Charles were treated properly" and to make "those scenes as potent as you can imagine them."

The confrontation between Tyrion and Shae was particularly harrowing for Kekilli, who compared the couple to Romeo and Juliet. "As an actress, I can't think like a fan or like Sibel. So I had to understand why Shae's behaving like that," she said, admitting that she also struggled with playing the scene in which Shae betrayed Tyrion and Sansa (Sophie Turner) during the Imp's trial.

"I really think that Shae loved Tyrion, truly, honestly ... but every time in these four [seasons], something happened [between them]. He had to hide her from his father; he married another girl ... it was like a knife in her stomach. When he said 'I have to marry Sansa,' every other woman would say 'go to hell,' but she was there for him and for [Sansa]. And then Tyrion gets colder and colder in behavior, and more tender to Sansa. And Shae isn't stupid, she knows that he's afraid of his father, but at some point, you don't think anymore, you just react. It was like taking that knife back and punching it in his stomach [instead]."

Still, Kekilli admitted that filming her death scene was a particularly emotional day -- which was made even more painful because Tyrion cried during the confrontation. "We had dinner one day before, with Dan, David and Peter, and I told them, 'I'm not coming to the set tomorrow. I'm sick.' And they were like, 'Yes, Sibel, of course. But you have to do it!' And then they promised me that I can come back as a zombie," she chuckled.

From a character standpoint, however, Kekilli said that she could understand Shae's motivations in ending up with Tywin: "After the trial, what kind of possibilities did she have? She's a prostitute, she's where she was before she met Tyrion. She's lost all her hopes, and she learned in her life to stay alive and to just trust herself ... You have to choose the most powerful man at that moment, and she did that."

The actress, who hails from Germany, did take some satisfaction from the fact that her death was shortly followed by Tywin's -- which was fittingly ignominious, taking place while the Hand of the King was on the toilet. "It was like, 'okay, if Shae has to die, she's taking the most powerful man with her,'" she admitted with a laugh.

In the end, Shae was a victim of her own circumstances, but Kekilli praised showrunners Benioff and Weiss for adding more layers to the character. "They really wrote well for Shae. They promised me at the beginning ... because I said, 'I read something about Shae on the internet; she's really superficial and she hasn't any depth.' They promised me they would change that, and they did it. I'm really grateful for that," she said. "Even though I knew that it would end not very well for her ... she was four years loyal, and she's a really proud woman. She's like, 'Hey, if Tyrion wants to leave me, he has to say it, he has to face me.'"

She added, "At the beginning, she was a prostitute, and she was interested in what she would get for [their relationship]. She was always straight with him. And then they grew with each other. She started to love him, and he started to love her ... There was nothing about playing a game with each other. I think every woman has to understand her situation. She's a low-born girl. It was like, 'Oh my God, I've found someone I love, and he loves me, even though I was a prostitute.'"

In the quest for the Iron Throne, Kekilli had no hard feelings towards Shae's former lover: "Even though Tyrion is a Lannister, and even though Tyrion killed Shae, I wish he would be the king, with a zombie Shae," she laughed. "With teamwork from Daenerys and Arya."

In terms of where the characters might go next season, Graves could only compare "The Children" to the first season finale, "which was an incredible piece of work by Alan Taylor, where every beat in the hour, every single scene ends up becoming a tectonic shift in the show."

Graves won't be a part of season five of "Thrones" (although he plans to return to the director's chair for season six) admitting that he had to take a break from the sprawling series because "it's so creatively immersive that it's almost dangerous ... you fall very, very quickly into an extremely obsessive state about the details and everything -- you just need to pull out of it once in a while."

Luckily for viewers, we only have to take a break until next Spring.

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