[Warning: This story contains spoilers for the sixth episode of Game of Thrones' seventh season, "Beyond the Wall."]

Daenerys Targaryen (Emilia Clarke) deserves all the credit in the world for bringing dragons back from beyond the brink of extinction — but at least some credit belongs to director Alan Taylor as well, as the man who helmed the birth of Drogon, Rhaegal and Viserion all the way back in season one. Now, Taylor can add "dragon-slayer" to his list of Game of Thrones accomplishments.

Taylor, an essential member of the Thrones director roster in the earliest days of the HBO series, returned for his first episode since the season two finale with this past week's "Beyond the Wall," the action-packed installment in which Daenerys loses one of her three dragons in battle against the Night King. It's a brutal sequence, which required shooting across multiple countries and coordination with multiple teams, but the actual act of killing off a fan-favorite character? It's nothing new for Taylor, given how many fan-favorite characters he's killed in the past, including Ned Stark (Sean Bean).

For more on the episode and destroying a dragon, Taylor spoke with The Hollywood Reporter and revealed secrets from "Beyond the Wall," including the fact that he's at a loss about that shocking scene involving an opening eye — and no, we're not talking about the zombified Viserion's eye, though that was a stunning development in its own right.

You were the director who first brought the dragons into this world, and now you're the director who took one of the dragons from this world — or changed one of the dragons, anyway. Did you feel the journey coming full circle in that way?

It couldn't have been better in that way. I was there giving birth to them in the first season, and then I went away from the series for quite a while. To come back and be able to finish that story, so to speak ... which, really, isn't finished, because now it's a new transformation of the dragon. But giving birth to them and being the first to kill one off felt dramatically wonderful. Also, the experience of going back and seeing how much all of these characters have evolved, too, like Sansa [Sophie Turner] and Arya [Maisie Williams], who have both grown up since we started. It felt full circle in a lot of ways.

What are the challenges involved in filming the death of one of the longest-running and most beloved characters in the series, albeit a character who doesn't have an actual physical form? 

Well, when I read the script for the first time and realized what we were about to do, I was very grateful. I have a history of killing beloved characters on HBO shows. I killed Ned Stark, I killed Julius Caesar [on Rome], I killed Wild Bill Hickok [on Deadwood], I killed [character name redacted because this is a terrific final season twist that should not be spoiled even 10 years later] on The Sopranos ... I don't think I'm forgetting anybody. As a director, it's great when you have a moment like that, because you know it's going to have an impact when a character has been established in a way that you've been invested in them. I knew that killing a dragon was going to be like killing a puppy. (Laughs.) It's an emotional moment when you kill a character that's flesh and blood and human, but killing a creature that's beloved the way dragons are? I knew it would have impact and be a game-changing thing. I was grateful to be able to do it. 

It takes a village to kill a dragon, because we're working with tennis balls on sticks and greenscreen lumps and rigs that can blow some interactive fire, but then Joe Bauer and his visual effects team make it really breathe and come to life. It's a huge collaboration. We're all depending on storyboards and pre-viz to have the cast understand what's going on, since they don't have the actual creature to interact with.

How much of the onus is on Emilia Clarke and the other actors to convey the necessary emotional weight of losing a dragon?

It's a key point. We provided the shots where we knew the dragon was going to be impaled and crash. There are some shots that were deliberately elegiac and emotional, like when he slides into the water. So much of it is cross-cutting the faces as they watch this action unfold, so we have reaction shots all along the way from the moment of impact, barreling toward the water, and finally sinking into the ice. Of course, that emotional cross-cutting ends on Emilia, because it's her baby that's gone down. I think she did wonderful work, given that she was working off of a tennis ball in that moment. And then we cut to Jon [Kit Harington], who is filled with fury. It's a great pairing of those two emotional reactions.

Courtesy of Helen Sloan/HBO

There are some people wondering about the timeline of the episode — how Gendry [Joe Dempsie] could reach Eastwatch, then send a raven to Dragonstone, have it reach Daenerys and have her travel up to the island on the frozen lake, all while Jon and his allies are still out there. Did you and the writers have conversations about the timing of events?

We did. We did a few things, like getting deliberately hazy about how much time is passing, because it's so dark in the frozen lake and you don't know how many days or nights you may have witnessed. We tried to make it a little ambiguous and give it some wiggle room on that end. We were aware that we were asking for people's suspended disbelief — plausible impossibilities is what you're aiming for. But I did read one review where they could just not get over the flight time of the raven, and that ruined the show for them. (Laughs.) If that's the way you're watching the show, I'm sorry it's not working for you! I hope somebody will argue back with the exact kilometer distance between Eastwatch and Dragonstone, and just keep the argument going. I'm sure [creators-showrunners] David [Benioff] and Dan [Weiss] have some idea that it's logistically possible, but for some people, it was a strain to believe all of that.

The episode ends on the dragon's eye going ice blue, but some fans have noticed a different shot of an eye: one in which the direwolf on the hilt of Jon Snow's sword Longclaw opens its eyes. What's the deal?

(Laughs.) That's our fan base working very, very hard on our behalf. I think that's a fan-created moment, I have to say.

I thought so, too, but I went back on HBO Go, and it's real. You see Longclaw's eye is white, and then it reveals a pupil when Jon emerges from the water.

Well, they pulled a fast one on the director, then. I had nothing to do with that! Maybe Longclaw is actually magic and just doing something on its own now. I'll have to go back and look now that you've highlighted that. I hadn't even heard about it. I'll have to go back and look and see if I can figure out what's going on.

[Editor's note: Watch Longclaw's eye open in the video below.]

Can you describe what it's like to work with Vladimír Furdík, the stuntman who plays the Night King?

He's a delight. I've worked with him for years now. I worked with him on Game of Thrones, and then he was on Thor: The Dark World. He was our villain stunt person, in full prosthetic makeup. He's just delightful. There's nothing he can't do. He's a full-on actor in that role, aside from being able to do all of the action and all of the horse work. He has a beautiful face — although you lose some of that behind the Night King prosthetics. ... There's a lot of surreality, though. It's weird seeing him as the Night King, and then walking around the set of the frozen lake, passing a bunch of very dead zombies who are talking about what they're going to do on the weekend, smoking cigarettes. It's constantly jarring. (Laughs.) Just having White Walkers hanging around ... they're looking at you like you're going to die, and then you ask them if they can move over there, and they go, "Certainly!" And they shift over. It just doesn't seem right that they're willing to do what you tell them.

What was involved in filming the scene where the wights fall into the lake of ice?

That was a big deal. We were in Iceland for a great deal of the episode, thank goodness, but the frozen lake itself was not in Iceland. It was not going to be practical or safe to be on a frozen lake in Iceland and drop people into the water. We were on a huge quarry that we paved outside of Belfast, so every moment of interaction with water had to be a multiple stage process where we filmed the action on our 360-degree set and landscape, and then restage it against greenscreen with elements we shot in a dunk tank rig, and all of those elements get married together to form something as simple as a guy falling into the ice and plopping into the water. That was one of the most striking things about being away from the show and coming back, the scale of things evolving so much. There were four or five shots required in order to make that happen. We were not doing anything like that in seasons one and two. 

Jon and Daenerys are growing closer together. What's that like for you to see and be involved in bringing to life, given your view of the series as someone who's been involved since the very first season?

It's funny, it really did have a real scale to it for me. I remember being on location in season one, on location in Malta with George R.R. Martin, when he was visiting. At the time, we had no idea what the show was going to turn into. We hadn't gone public yet. He was quite open about what his plans were, in a way we certainly haven't been since, since the show has become a big deal and has to be kept secret. But even then, in that first season, when there were 100 characters and we were finding out who was important and who was going to last, and no one knew if Robb Stark [Richard Madden] was going to wind up being king or something — even then, he said very early on that this was going to be about Dany and Jon Snow. It was a revelation to hear so early on, because they were secondary characters, or at least they were characters among many other characters, and it wasn't clear yet where the story was going to head. From the beginning, he knew this relationship was going to be the focus. The actors have known about it for a long time, and seeing them together, they've played beautifully off each other. They know each other so well that it's almost effortless in terms of their performance.

Watch the video below for the Game of Thrones cast's preview of season seven's battles.

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