'Game of Thrones' Director Reveals Secrets Behind Season Finale's Most Explosive Moment

'Game of Thrones' Season 6 Finale 15 - Publicity - H 2016

[Warning: This story contains spoilers through the season six finale of HBO's Game of Thrones, "The Winds of Winter."]

As if there wasn't already enough carnage on the battlefield outside Winterfell, director Miguel Sapochnik went ahead and followed his bloody "Battle of the Bastards" with the Westeros equivalent of a nuclear bomb.

The veteran Game of Thrones director, also responsible for season five's "The Gift" and unforgettable "Hardhome," helmed the season six finale with fiery fury, quite literally in the case of the opening sequence: Cersei Lannister's (Lena Headey) act of terrorism, destroying King's Landing's historic Sept of Baelor with a massive supply of ferocious wildfire. The scene plays across the first 10 minutes of the finale and beyond, with dread mounting more and more through lethal children, deadly discoveries, and desperate crawls through the darkness — all stitched together by series composer Ramin Djawadi's haunting score.

In executing the sequence, Sapochnik tells The Hollywood Reporter that there was one key element to determine before anything else: the tone.

"When I first read it, I wondered how we would do this and avoid it feeling cheesy or cheap," he says. "After all, blowing everyone up in the third act isn't uncommon in Hollywood action movies."

With that in mind, Sapochnik and the Thrones team looked at a few specific references to guide them toward the proper climax, including one big-screen hero who routinely runs into explosive situations.

"The first thing that came to mind was making the explosion more like a James Bond movie," he said. "Sometimes they actually used to blow up the sets they'd built, and then use miniatures for everything else. There was always something so satisfying about that for me as a kid." 

The second inspiration was much less blockbuster-oriented, but no less large in terms of its place in popular culture: The Godfather Parts I and II.

"I loved the way things intercut on those [ending] sequences," says Sapochnik, "and although I know that inter-cutting isn’t really considered Game of Thrones, I felt like it was going to be the most effective way of telling this story."

Sapochnik pitched those touchstones to showrunners David Benioff and Dan Weiss, and began applying them to the demands of the "trial by wildfire," as it's come to be known among some fans.

"We went through a series of iterations, trying to tie in the actual moment of the explosion and what exploding wildfire would be like, what the delay from the moment of ignition to it reaching the sept would be, and then we pre-[visualized] the big CGI-heavy moments so that we could break down which elements would be shot where."

The scene was shot at multiple points across multiple locations, but the majority of filming took place on a soundstage in Belfast, Ireland. While one might think creating the wildfire explosion would be the trickiest aspect of the scene, it turns out the practical shoot on the sept stage was even more challenging.

"It's a funny set because there's only ever been half of it built," says Sapochnik. "If you want to shoot 360 degrees you have to pretend you've turned around, but just mirror where everyone is standing. This is a complete clusterf— for continuity, because usually you end up doing it later in the day, and if you've ever wondered what 350 people look like when they're scratching their head, really confused, trying to work out their blocking after you've told them their rights are now their lefts, try switching directions on the sept stage.

"At the end of it, we had to get a series of plates of all the extras reacting to the explosion, and I have to say that was fun," he adds. "The extras were great."

Also great: Cersei herself. When the wildfire erupts and the dust begins to spread and settle, the queen mother (and soon to be queen proper, due to her son's suicide) watches from a distance, her smirking face flush with satisfaction. Moments later, she confesses to Septa Unella that she's never felt such pleasure in her entire life; it certainly shows on Cersei's face as she witnesses the deaths of the High Sparrow (Jonathan Pryce), Margaery Tyrell (Natalie Dormer) and more from afar.

"Lena is pretty sharp when it comes to charting her own arc," says Sapochnik, adding that she required very little direction. "The thing we discussed the most was how to react to the sept's destruction. This was mainly because there was obviously no sept, just a huge bluescreen with a bunch of dots on it and a fan and such to create a shockwave. With such a big event taking place, having nothing there to see or even interact with complicated what in the end was already a complicated enough emotional response. So I would talk her through what was happening in each take and she'd react accordingly. Lena does not need much hand-holding. She brings her A game to work. Mostly you just have to get out her way and let her do her thing."

Headey wasn't the only one who brought her A game to "The Winds of Winter." Sapochnik, already responsible for one of the most elite episodes in Game of Thrones history before entering season six, one-upped himself with two back-to-back installments loaded with more than their fair share of dramatic wildfire. But much like the Battle of the Bastards, crafting the final two installments of season six was a grueling effort, hard-fought every step of the way.

"The biggest challenge was actually getting it done without getting ill or oversleeping and being late to set — my worst nightmare," says Sapochnik. "It may sound silly, but as a director on this show and with so little time, getting ill is the worst because you can't just stop and take the day off. You have to suck it up and keep going. And usually that means putting your waterproofs on and your wellies and getting back out there come rain, sleet or snow."

No word on fans of rain or sleet, but Snow enthusiasts certainly appreciate the effort.

Relive the season six finale's best moments in the video below:

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