Books 1 and 2 of 'The Legend of Korra' didn't have time for episodes like “Original Airbenders.” The closest half hour might be “The Sting,” last season's Korra-less, Mako detective tale. It was an exciting deviation from the stream of plot-driven episodes ... at least, it was in theory. “The Sting” was still adding stepping stones for how Book 2 would wrap everything up. “Original Airbenders” is essential without feeling concretely tied to any big picture, Zaheer's nefarious motives or everything Korra's dealt with in Zaofu. Much like 'Avatar: The Last Airbender,' 'Korra' strays from the path to detail its well-worn characters. It's a breath of fresh air(bender).

'Harry Potter' fans should appreciate the Hogwartsian misadventures of the fledgling Airbenders, thrust into the spotlight for this Tenzin/Jinora/Bumi-centric episode. Adjusting to his new professorial duties, Tenzin comes off as a McGonagall: diligent, traditional, and a little bland. His tales of Airbender history put the crowd to sleep. Society has modernized, but in Tenzin's eyes, Airbender philosophy remains steadfast. Even Tenzin is tired of how his class is going; one Hermione-like student (named “Otaku,” one of 'Korra''s many nods to fandom) delivers all the answers as the rest of his classmates melt into puddles. Training the first wave of Airbenders in 100 years is going poorly.

Korra, calling from Zaofu, has some ideas: let the energetic people inject a little life into the lecturing. "Conflict resolution, it's what I do,” Korra says, baffling most 'Korra' fans (I'm going to need a list of examples backing that one up, Avatar). Tenzin takes the words to heart, enlisting Bumi to give his teaching style a militaristic kick in the butt. The advice turns him from a McGonagall into a Snape. He puts his students through the ringer, first with a balancing act and then the 'Korra' equivalent of 'American Ninja Warrior.' At one point, he wakes up his troupe with a vuvuzela — the ultimate annoyance. No one can convince him he's doing it wrong; The Airbenders must learn and they must learn now. J.K. Simmons is the actor to unearth these uncharacteristic, fluctuating behaviors. In Book 1, Tenzin was an absolute Airbender, as if the wind could flow through him even at the toughest moments. Forever at peace. Here, he's off-kilter. He's instructing like an Earthbender. It's not his way, so it doesn't work.

As Tenzin grapples with wandering minds, Jinora strays away long enough to taste independence and hunger for more. “Getting into trouble” is that paradoxical part of life that could kill you while being completely vital to a well-adjusted existence. To grow is to enter the world unprepared. Kai opens that door for Jinora. Continuing the blossoming relationship, the two decide to take a mini-date out into the Sky Bison fields. It's lush, robust, and unexpectedly dangerous. Mama Sky Bison will chomp your head off! Jinora saves her lovable scamp from death-by-Bison-bite, prompting an adorable compliment: "You know, you're an incredible Airbender ... If anyone's a master, you would be”

Jinora not having her Airbender tattoos is like an American teenager not being able to date in high school because ... well, just because. The strain of Tenzin's overbearing, protective parenting finally shows its face, both in Jinora's spiritual practices and in her love life (later in the episode, someone refers to Kai as Jinora's boyfriend and Tenzin nearly poops his pants). Luckily, life steps in to prove Jinora a capable adult and Tenzin a wayward teacher.

While visiting the temple countryside a second time, Sky Bison poachers capture Jinora and Kai. There's nothing grislier than juxtaposing adorable baby animals and poachers who wear their skins with pride. These guys are AWFUL. More disturbing: The poachers collect food for the Earth Queen, who apparently ate 'Avatr: The Last Airbender''s Busco the Bear. That ain't right.

But in the face of danger, Jinora plays it cool. She knows immediately what to do: Make contact with a spirit, send word to Bunju the Spirit Bunny that something is wrong, and get the Airbender forces to rescue her and Kai. The plan works: with Bumi at the battalion’s front, the rough-around-the-edges Airbenders launch a surprise attack on the Earth Kingdom henchmen. Airbending action is still fresh for the 'Avatar' universe — we've never seen what 10 Airbenders can do when their powers combine. Unlike how the 'Star Wars' universe felt an imperative to expand Jedi powers as the brand's scope grew and grew, there's consistency to these fights. Mel Zwyer weaves together combos of devastating gusts, whirlwind punches, and air ball deliveries that arrive with tremendous force thanks to imaginative animation. When Tenzin joins the fight, aiding Kai in taking down the lead goon, it's like a scene out of 'Raiders of the Lost Ark.' Tenzin isn't just taking down enemies, he's complicating his own character with every blow. He warns Kai not to strike the defenseless poacher, but adds that the kid has nice form. It's a nice capper that puts the “Change” in Book 3: Change.

“Original Airbenders" avoids any forced mention of Zaheer, the Lin/Suyin saga, or further world-building distractions. The camera is squared on these people we love and want to see grow. Tenzin's telling Jinora that he'll consider letting her get tattoos is a huge step. More so, Bumi's relationship to his brother. He admits to never feeling like part of the Air Nation, even as Aang's son. Tenzin knows he was part of the problem. But not anymore. “You are now,” Tenzin tells him.

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