If you haven’t caught up with the latest episode of Game of Thrones, “The Long Night”, don’t worry; no major overarching plot points or character fates will be spoiled here.

From the opening scene of HBO’s mega popular Game of Thrones’ pilot episode, which saw a trio of rangers discovering mutilated corpses right before being attacked by undead creatures, horror has been a major element of the fantasy drama series. As the political maneuvering and battling for the Iron Throne in Westeros was only just beginning, so too was the war being waged on the living by the icy Night King; the humans just didn’t know it yet.

For seasons, we watched as the Night King and his White Walker generals slowly made their way across the land North of the icy wall that separates the wild from the rest of civilized Westeros, slaughtering unsuspecting native people and turning their corpses into reanimated soldiers for his campaign to snuff out humanity. With all of the final story pieces clicking into place in the series’ final episodes, the culmination of that silent, deadly war delivered the shows’ longest episode to date…. and it was an intense, feature length horror movie.

The first ten minutes of “The Long Night” created unbearable tension; it was mostly devoid of dialogue as it focused on ambient sound instead while we watched the characters we’ve grown to love (or hate) steel themselves for the battle ahead; the massive army of undead was about to arrive at their doorstep. The tension already coiled so tightly, and the fighting hadn’t even begun.

With the enemy still unseen, off in the distance well hidden by the pitch-black night, the fiercest Dothraki warriors charged toward them on horses with their fire-burning swords as the first wave of attack. The rest of the troops looked on in horror as they watched those far off flames get snuffed out in the dark, one by one; only a few made it back by fleeing in abject terror. If it hadn’t hit home just how horrific this undead army was, the characters grasped it now.

“We’re fighting death! We can’t beat death.”

Once the undead finally arrive at the gates of Winterfell, it becomes a harrowing fight to survive. The plan, of course, was to end humanity’s biggest threat once and for all, but that devolved quickly into simply trying to make it out alive. This undead army feels no pain and doesn’t need to stop for any reason. They don’t tire like humans, and their numbers are endless. This was the relentless zombie horde attack that World War Z should have been.

For much of the episode’s run time, it’s watching our characters getting pummeled by an unyielding undead army- all in various stages of decay. The battle is unnerving in itself as we see some of our favorites cry out in agony and exhaustion, while others weep and cower in fear, all the while so much blood is being spilled across the snow. And because all nonstop action films need moments that allow the audience to catch their breath, well, “The Long Night” decided to use those quiet moments to ramp up the fear instead.

Just about every major zombie film or show has a sequence that sees its protagonist(s) being forced to tiptoe around an enclosed space occupied by the undead so they can make it out without attracting unwanted attention. “The Long Night” gave us that sequence in the Winterfell library, late in the episode. With the humans’ only safe haven now inundated with the undead, young Arya finds herself alone and surrounded. She hides behind the bookshelves, sneaking around the shuffling zombies and trying to avoid catching their notice. It results in a taut, suspense-filled hide and seek game between Arya and one particularly eerie wight.

Another major standout scene in this horror-filled episode took place in the crypt. For the humans unable to participate in the battle- the children, women, elderly, etc. – they took refuge beneath the castle. Which happens to be the family crypt. It’s a tactical move that seems tenuous at best, especially from a horror fan’s perspective, considering there’s only one way in or out. That hints at a bloodbath waiting to happen. And it does. But the invading undead don’t come from above, but within. The long-buried dead ancestors are awakened, skeletons and all, to attack the most vulnerable. The reanimating corpses digging their way out of their dirt-filled tombs provided some of the best horror imagery of the episode.

All 82 minutes were stuffed to the brim with unmitigated dread, unrelenting terror, and suspense-driven action.

From quiet intensity to boisterous, pulse-pounding fights for survival, “The Long Night” made for what was essentially a satisfying feature length horror movie. Because the episode is action and horror-centric, you could tune in solely for this episode and not have to worry about the usually complicated plot. If you’re not watching, you’re missing out on a great show with enough genre elements to appease horror fans like ourselves.

There have been epic battles before in Game of Thrones, but never has the enemy been as scary as it was last night. If you see just one episode, make it this one.