In case you haven't logged on Facebook or Twitter or encountered another human being yet this morning, know that Sunday night's (May 31) episode of "Game of Thrones" shocked viewers and book-reading viewers alike with an epic, 20-odd minute battle sequence at Hardhome -- the seaside Wildling settlement that also served as the episode's name.

In the sequence, Jon Snow (Kit Harington) and Tormund Giantsbane (Kristofer Hivju) tried to convince the Wildling army that it was worth their efforts to combine forces with the Night's Watch to fight the White Walkers... only the White Walkers got to them first, devastating their numbers and turning their dead into yet even more mindless fighters for the Ice Zombies that terrorize the north.

It was the first time we really got to see the extent of the Walkers' devastating powers, and was a great showcase for Harington as he fought a leading Walker one-on-one, learning that Valyrian steel is one of the few things that can defeat them. Still, Jon Snow and the Wildlings undoubtedly lost (as you can see in the game-changing GIF below), and what happened in "Hardhome" should greatly impact the show going forward as more attention is (finally!) paid to the biggest threat to Westeros since the Mad King Aerys.

MTV News spoke to "Hardhome"'s director, Miguel Sapochnik, over email following the episode, finding out first-hand what it's like to direct the series' first major non-book-mandated battle sequence... and apparently, worrying about what George R. R. Martin did or did not write was the last thing on his mind.

"I haven’t read the books so I didn’t have to worry about what was and what was not in them," Sapochnik said. "I got the outline document for the sequence first, and then spoke to Dan [Weiss] and David [Benioff] to get a sense of what they wanted to get out of the piece overall. I think it’s important to know what you’re aiming for. Then I just went off and tried to imagine it -- drew some stuff, wrote notes, listened to music.

"Usually I get an image in my head and I start building out from there. In this case it was Jon on his knees in the snow after defeating the White Walker. At the same time I look for an emotional and dramatic spine to the sequence, whatever it is. In this instance it struck me that this is not a battle...it's a massacre. Instead of just an action sequence, I wanted to make it a tragedy.

"So with this in mind I just started breaking down the sequence into acts, then story lines then beats, and slowly deconstructed it until it was in bite-size chunks; pieces I could get my head around," he continued. "Then I put it back together, checking as I went along that the spine was still there. Along the way there were many changes and many obstacles, but you just have to stay focused on telling that story, following the characters and setting the tone."

These obstacles, Sapochnik explained, included a grueling 15-day shoot in Northern Ireland -- which is used as Westeros' northern locations for a reason. There were only 8 hours of daylight available for scenes that warranted 10-12, and per Kit Harington's recollection of the battle in EW, the CGI elements meant that they were only getting about a minute of footage shot per day.

"We were racing everyday to complete our work before it got dark," Sapochnik continued. "Oh and yes, it was cold."

Lucky for Sapochnik, Harington -- who also told EW that he filmed each fight three times, once with his opponent in a greenscreen-projectable suit, once with his opponent in full-on scary makeup, and a third time with no opponent at all; swinging at open air -- was a great sport. The actor "did pretty much all his own stunts bar being flung across a room with a sword in his hand," though the director also noted that they were "just glad to get to the end of each day unscathed."

Having such a dedicated cast undoubtedly helped Sapochnik focus on the particulars of the battle -- being that it featured zombie-like creatures in the age of "Walking Dead" mania, "Thrones" had to make sure to differentiate their monsters from both the White Walkers that control them and other popular media zombies.

"Movement was a big thing," Sapochnik explained, "Making them feel like they swarmed where possible. The writers wanted to distinguish them as not zombies. They are puppets for the Night's King. And they don’t think; [they] just pick a target and go after it until it’s dead, or they are cut into enough pieces they can’t chase it any more. Once you have the rules you just apply them to every beat, and see where it takes you story-wise."

Of course, one of the elements that stood out the most story-wise was Karsi, a Wildling warrior woman (played by "Pitch Perfect 2" star Birgitte Hjort Sørensen) who managed to show up in the battle's first act, steal viewers' hearts with her headstrong determination and courage, then break said hearts when she was eaten by a gaggle of dead children. According to Sapochnik, this unforgettable scene almost never came to pass -- because Karsi was initially a man.

"She was a guy originally, and then somewhere in the process we thought it might be cool if she were a mother, and show her sending off her own kids to make that moment with the corpse children really resonate emotionally," Sapochnik explained. "As the sequence was refined, she emerged as this clear representative of all the Wildlings, which was organic, and it made us care. Then we started casting and saw Birgitte's work and she got the part."

Overall, it's pretty safe to say that Sapochnik can sit back and relax now that "Hardhome" has aired -- viewers and fans alike seem to be thrilled (on social media, anyway) with the unexpected battle. And at least during the tougher, colder, battle-planning moments, Sapochnik could rest his mind knowing that his warm and sunny scenes with Emilia Clarke and Peter Dinklage were on their way.

"[There was] a bit of nerves, a bit of searching for the right tone, but they are both excellent actors and as they found each scene, they locked in and then it was just a case of sitting back and watching them do their stuff!" Sapochnik said.