Explaining danger is easy. Roland Emmerich is a master of insisting peril. In one of his signature disaster movies, a brainy government agent will babble some pseudo-science, then we’ll see the first of many tidal waves/earthquake tremors/alien attacks, and our brain politely understand: The world will end. Tricking audiences’ senses into feeling danger is more difficult. A movie like ‘Gravity’ taps immediacy and scope to whisk us out of the theater and into catastrophe. ‘Breaking Bad’ reminds us there are never rules, that anything can happen to anyone and at any time. It’s the difference between ‘Independence Day’ and Steven Spielberg’s ‘War of the Worlds’: Blowing up the White House is crazy, but blowing up the main character’s home, his neighborhood, his memories, makes the heart sink.

When Kuvira’s towering war machine lumbers into silhouetted view for the first time, ‘Legend of Korra’ strikes tangible fear. There’s tremendous payoff to the apocalyptic moment; With Varrick’s technology and the Korra Kaiju previously established Korra Kaiju, there was room for the show to go full Gundam from the beginning of Book 4. Instead, moral questioning transformed the show’s final season into a thinly veiled World War II allegory, complete with an unstoppable force. Anime legacies fuse with mankind’s history — for all its aesthetic awesomeness, we implicitly understand that this BFG laser cannon is a device capable of destroying the very soul of this world. A blast emits the sound of the Gods. Playing with fire is over. The world is about to be scorched and there’s not much a hero can do to stop it. The inevitability rattles the bones.

“Kuvira’s Gambit” opens with an inspirational rally on the wrong side of the line. So this is what it felt like to be Indiana Jones at the Nazi rally in ‘Last Crusade.’ Director Colin Heck channels his inner-Leni Riefenstahl to empower Kuvira’s Republic City-crushing speech, then immediately humanize her in a rare, intimate moment with Bataar Jr. As with even the most expertly crafted propaganda, there’s something sinister in the air, no more apparent then in Kuvira’s unsettling hug close-up. That is the warm, fuzzy smile of a sociopath, ladies and gentlemen.

By cluing us into Kuvira’s plans, writer Joshua Hamilton leaves even the most confident Team Avatar scenes floating in dread. Gliding back over to Republic City, our good guys learn from the recently-rescued Zhu Li that they have two weeks to prepare a defense against the incoming attack. President Raiko and Prince Wu crank the underway evacuation up to “mandatory.” They have a countdown. Varrick has a fleet of flying mech warriors in need of finishing touches. General Iroh is already arriving with his fleet. Team Avatar knows about the spirit vine-powered laser — so they’ll cut the rail lines and prevent it from getting anywhere near them. Korra vows to defend her home: “I won’t let Kuvira take the city.” Kuvira may not appear throughout this rallying stretch, but she’s there. The opening scenes reverberate through this later action, the Great Uniter looming over it all....

Team Avatar’s decision to cross enemy lines ‘Kelly’s Heroes’ style, made me think that, maybe, Korra could finally get a jump on Kuvira. There were just enough gun-ho patriotic moments — Prince Wu’s “going to the bathroom” speech, Pema standing by Tenzin in the face of the unknown, Zhu Li reuniting with/schooling Varrick — to dampen the incoming reality. Hamilton’s seamless transition between hope and Hll was sublime; Within seconds of Korra’s last word, Kuvira emerges from the moonlit horizon and Death Stars (it’s a verb) innocents into oblivion. Korra, Bolin, Mako, and Asami swoop into action after the commercial break only to meet the same iron giant. “I know what happens next,” Bolin exclaims. “We’ve gotta get out of here now!” Where’s Big O when you need him?

Details make this more than an Emmerichian spectacle. A peek inside the mech reveals Kuvira’s elegant metalbending skills at the controls, psychically pulling levers and dictating its every move. When Kuvira sends a spirit energy beam blasting through a military outpost, the attack stems directly from her, not faceless minions. She’s truly maniacal now. Benjamin Wynn channels the deadlier-than-ever characterization through his sound design. We previously heard laser beam sounds in Korra’s throw down with UnaVaatu, but that was at a wide distance that could contain two spirit giants. Abord a fleeing Oogi, the beam comes beyond earshot to deafening levels. The reverberation crackles through the picture. It’s the sonic version of Michael Myers swiping with his blade and nearly slashing Laurie across the arm.

Kuvira’s ambush throw President Raiko into a tizzy. Even during Zaheer’s run of anarchical terrorism, we’e never seen this kind of chaos ensue, and we rarely see it in television. Characters acting frantically, scared for their lives. Even the stagnant animation of Pema and Wu rushing citizens on to outbound trains adds to the psychedelia of being totally knocked off one’s rocker. After “ordering” the dictator to stand down, only to see KuviraZord blow away Iroh’s naval fleet, Raiko has little choice other than standing down. “We surrender,” the President says with exhausted defeat. This reignites Korra’s original idea — maybe there are still smaller-scale options, ways to blow Kuvira’s plans up from the inside.

Kuvira’s love for Bataar Jr. is an oft-debated topic in the corners of Tumblr. Is she being sincere? I believe she was. How deep the passion is a different question. Kuvira’s rebellious fiancée turns out to be the “gambit” of the episode, a sacrificial lamb, disposable if and when necessary. As her diplomat, Bataar Jr. heads to Air Temple Island to negotiate the terms of surrender with President Raiko. He doesn’t make it. Like ninjas, Korra, Tenzin, and Bumi slam and bag Su’s kid, bringing him in for interrogation. Korra nearly Avatar State’s his sorry bottom to get answers, pulling back last minute (someone read that C.I.A. torture report!). Bataar Jr. manages to become even slimier in this moment: “I know an empty threat when I see one.” Not even teary-eyed Su can plead with enough emotion to woo her defector son away from the power-hungry Kurivra (a lovely bit of acting from Anne Heche).

Korra’s back-up plan has mixed results. If Bataar Jr. won’t talk, Korra will make sure he never sees his beloved Kuvira again, continuing to haul him around as a prisoner for all eternity. Sounds like a real pain, but hey, Korra’s dedicated. This breaks Bataar, who rings Kuvira for assistance. Turns out it’s the trembling pawn who winds up helping her. “The only thing that matters is that we’re together for the rest of our lives,” Bataar says. Kuvira actually agrees, looking a little verklempt over the whole thing. A show. Kuvira traces the phone call — let’s assume Earthbenders can feel the location of incoming calls the same way Toph can pick up on spirit vine movement, shall we? — and locks her weapon on Team Avatar’s location. Kuvira chooses world domination over smooching with Bataar Jr.. If Korra wanted to snap the guy out of his allegiance, that should do it.

Kuvira’s final blast rips through Varrick’s flying mech factory. The hummingbirds will not hum. It also blasts Korra like she’s Ethan Hunt in a Mission: Impossible movie, flying towards screen and just avoiding ground zero. It’s hard to imagine anyone sustaining life-threatening injuries in the surprise attack — with only one hour-long episode left, that’d be an unceremonious way to go. More likely: Bataar, scorned by his luuuuvah, teams with the good guys to ground Kuvira’s WMD. Will Republic City go up in flames first? Will the spirits intervene? Will Korra go mano a mano with Kuvira once again? Will lives be on the line to save the day? In true Korra style, there aren’t too many Chekov’s Giant Spirit Vine Guns on the table, few telegraphed moves that the show’s final moments will make. The finale is one big question mark — the setup for thrills that we’ll feel.