- This article is about the first episode of the Book One: Water finale. For the second part of the finale, see "The Siege of the North, Part 2". For the battle, see Siege of the North.
The Fire Nation's massive armada prepares to attack the Northern Water Tribe at dawn. The Tribe readies its defenses, and Sokka volunteers to be a warrior after Yue explains that she cannot contact him anymore. With Iroh at his side, Zhao leads the invasion, battling Water Tribe forces for the entire day. Meanwhile, Zuko infiltrates the tribe on his own, seeking to capture Aang. Aang believes venturing into the Spirit World and speaking to the Moon and Ocean Spirits might give him the wisdom to defeat the Fire Nation. After Aang's spirit leaves for the Spirit World, Zuko manages to kidnap his body.
At the Northern Water Tribe, a sparring match is fought between an anxious young man and a confident Katara. After Katara swiftly defeats her opponent by encasing him in a tall ice formation, Master Pakku unceremoniously releases the student and asks the other students if any of them feel up to sparring a second time with Katara. Hearing no response from his already-beaten students, Master Pakku tells Katara that she has progressed faster than any of the others, and that her hard work and determination have paid off in ways that raw talent alone cannot do. Seeing Aang playing with Momo, Master Pakku cynically asks Aang if he wishes to face Katara, since he must have mastered waterbending already if he is playing with "house pets". Unconcerned by Pakku's tone, Aang responds that he would not consider himself a "master" but has something to show Pakku regardless and proceeds to bend snow around himself as if he were a snowman. This does not impress either Master Pakku or Katara.
Meanwhile, Sokka is walking on the ledge of an ice bridge as Princess Yue walks on the bridge beside him. She asks if there are any palaces in the Southern Water Tribe, to which Sokka replies, "I grew up on a block of ice. It's not exactly a cultural hub." As Sokka comes down from the ledge, Yue touches his shoulder and laughs at his statement. However, her smile turns to a frown, as she explains that what they are doing is wrong because she is engaged to another person. Undeterred, Sokka expresses that they are just friends and that he would like for her to meet another of his friends, Appa.
The two converse as they climb into Appa's saddle, and Sokka directs Appa into the sky with a dramatic "Yip yip". Yue is amazed and, wondering if it is always cold when flying, moves closer to Sokka, who softly replies, "Not when you're with someone." They look into each other's eyes and move toward a kiss, but when they realize what is about to happen, they blush and quickly try to change the subject. Looking around in embarrassment, Sokka notices that gray snow has begun to fall from the sky and becomes concerned.
At the Northern Water Tribe city, the same gray snow begins to fall. While Aang rolls in the snow around Momo, the lemur eats one of the gray particles and coughs it out, attracting Aang's attention. As the snow falls, Water Tribe citizens look on in wonder. Sokka and Yue land on a nearby glacier, and Sokka, examining the snow, tells her he recognizes it as the result of soot from Fire Nation ships mixing with snow, the same as the snow that fell from the sky when the Fire Nation attacked his village. He tells Yue the Fire Nation has closed in on the North Pole with a massive fleet. A huge gray mushroom cloud looms on the horizon.
Several Fire Nation ships sail through the water, and Admiral Zhao sinisterly tells General Iroh that they are in the process of writing history, as they will be destroying the last of the Water Tribe civilization. When Iroh warns Zhao that history is not always kind to its subjects, Zhao condescendingly assures him that this will not be like Iroh's legendary failure at Ba Sing Se; Iroh ominously tells Zhao he hopes not, for Zhao's sake. Zhao tells Iroh to tell the captain to prepare for their first strike, and Iroh departs. He finds Zuko, who is disguised as a guard in the bowels of the ship, and tells him they will be landing soon, inquiring if Zuko has a plan, to which he replies, "I'm working on it, Uncle."
Back at the Northern Water Tribe, a large drum adorned with the Water Tribe's insignia is beaten as citizens rush to the main gathering hall. As Sokka and Yue head up the steps, Yue abruptly stops to tell Sokka they cannot see each other because being around him makes her too confused, as she is engaged, yet likes him as more than a friend.
At the gathering hall, Chief Arnook tells the citizens that war is upon them and that it saddens him to know that some of those gathered before him will likely perishing during the coming conflict. Calling upon the Ocean and Moon Spirits to be with them as they fight for their existence, the chief asks for volunteers to engage in a dangerous mission. Sokka is first to volunteer, despite Katara's objections, and Yue looks on, fighting back tears in her eyes, as the chief paints a mark of commitment on Sokka's forehead.
Awaiting the first strike from the Fire Nation, Chief Arnook remarks to Aang that the stillness before battle is unbearable. In response, Aang admits that he was not with his people when they were attacked by the Fire Nation and vows to make a difference for the people of the Water Tribe. Finally, as the Water Tribe warriors look on, the first fireball is launched, striking the center of the Northern Water Tribe emblem on the outer wall, the force of its impact throwing many soldiers off their feet. As a second fireball lands in the heart of the city and a third approaches, Aang mounts Appa and flies out to face the Fire Nation Navy.
Several fireballs are launched by the lead ship, and as Aang approaches, he manages to deflect one fireball into the nearby ice cap. He leaps off Appa, expands his glider, and maneuvers between soldiers' fire blasts as he lands on the deck and sweeps away those attacking him. After disabling the fireball catapults on the lead ship, an attacking soldier traps him against a trebuchet by throwing chains at him. However, Aang is saved when Appa appears and grabs the attacker, throwing him overboard. As the ship is attacked by approaching waterbenders and immobilized, Aang leaps aboard Appa to head to the next ship and is shocked to see hundreds of Fire Nation ships before him.
Meanwhile, Chief Arnook addresses the men who had volunteered for his mission, revealing that they will be infiltrating the Fire Nation fleet disguised as their soldiers. Upon seeing Hahn present himself in an eighty-five years old uniform, Sokka laughs, and after sarcastically mocking the uniform, he points out a differences between the modern and old uniforms. When Arnook declares their first objective to be to identify the fleet's commanding officer, Sokka notes their target to be Zhao and is immediately told to bring Hahn, the leader of their mission, up to speed. Chief Arnook instructs Hahn to show Sokka respect, commenting that he expects "nothing less from [his] future son-in-law." Shocked by the revelation, Sokka insincerely congratulates him.
As night approaches, Iroh advises Zhao to cease the attack, as waterbenders draw strength from the moon, which is nearing its full phase. Zhao states that he is aware of the problem, and that he is working on a solution, but he agrees, in the meantime, to halt the attack until morning.
Returning as the ships cease firing, Aang is exhausted and frustrated. As Katara and Yue run to him, he tells them he was able to take out about a dozen ships, though doubts his ability to help the Water Tribe hold off the Fire Nation attack, as he is "just one kid" against an entire fleet.
Deep in the hold of Zhao's ship, Zuko has removed his Fire Nation uniform and is preparing for a solo journey into the Water Tribe city to capture the Avatar. Iroh expresses his concern for Zuko, saying that he only nags Zuko because since the loss of his own son, he sees Zuko as his own. Touched, Zuko acknowledges his uncle's statement and says he will meet Iroh again after he has the Avatar.
In the Water Tribe warriors' barracks, Hahn arrogantly explains to Sokka the perks of marrying Yue, which only serves to anger him, and further insults him by insinuating that he lacks the ability to understand the Northern Water Tribe's way of functioning. Enraged, Sokka attacks Hahn, calling him a "jerk without a soul". They fight until Chief Arnook pulls them apart, and Sokka is promptly removed from the mission.
Zuko maneuvers his kayak to the shores of the ice cap near the base of the Water Tribe outer wall, where he notices turtle seals diving into an opening in the ice. Knowing the creatures must come up for air somewhere; Zuko takes a deep breath and dives in after them.
As the nearly full moon hangs in the night sky, Yue tells Aang and Katara that the moon taught waterbending to the people of the Water Tribes as they observed its push and pull on the ocean. Hit with a sudden burst of inspiration, Aang realizes that the spirits might be able to help him save the Water Tribe. When Katara voices skepticism as to how he can reach them, Yue leads them to the most spiritual place in the North Pole – the Spirit Oasis, a verdant garden surrounded on all sides by towering walls of ice. Aang is ecstatic to see grass again, and Katara is amazed by the warmness of the air. Aang, sensing the tranquility of the oasis, begins to meditate at the base of the oasis pool, which contains a black and a white koi fish encircling each other.
Zuko manages to find an underground cave, which serves as the turtle seals's air pocket. He uses his "breath of fire" technique to ward off the chilling effects of the water and begins to work his way up an opening with water rushing through.
As Sokka sharpens his boomerang in the now-empty barracks, Chief Arnook approaches him and clarifies that he removed Sokka from the mission in hopes that he would accept to guard Princess Yue. Sokka humbly agrees to do so.
Zuko ascends to an air pocket in the freezing water and catches his breath. He spots another passage up under the water and heads through, but is met with an ice barrier. Using his firebending, Zuko melts the ice and breaks through into a passage within the city, where he stops for a moment to rest.
As Aang tries to meditate into the Spirit World, Katara and Yue's conversation distracts him, but after he shouts at them to be quiet, they comply. Aang focuses on the koi fish, and he finally enters the Spirit World after noticing the similarity of the two fish to yin and yang. Upon seeing Aang's eyes and tattoos glow, Yue asks Katara if they should get some help, but Katara says she can protect Aang. At that moment, Zuko suddenly walks in. Yue leaves to get help as Katara and Zuko duel. Zuko realizes Katara's skill level has greatly advanced from earlier encounters, and he is eventually encased in ice. However, as the sun rises, Zuko's firebending strength increases, and he manages to melt his way out of Katara's trap and overpowers her, rendering her unconscious by throwing her against a gate post with a fire blast. Standing over her motionless form, he notes that while she rises with the moon, he draws strength from the sun, before taking Aang's body and escaping from the oasis.
In the meantime, Fire Nation ships break through the Water Tribe's outer wall, and soldiers rush through the breaches to attack. Back on his command ship, Zhao states the city will fall today despite any efforts to fight off the inevitable.
Katara regains consciousness and discovers that Aang is gone. Sokka and Yue approach on Appa, and a distressed Katara tells them that Zuko has Aang. As they wonder where he might have gone, Zuko treks across the polar ice surrounding the city, carrying a limp Aang, who is still in the Spirit World, over his shoulder into a biting gale as snow flutters from an ominous, gray sky.
- Written by:
- Directed by:
- Also starring:
- Additional voices:
- Dee Bradley Baker
- Victor Brandt
- Scott McAfee
- Jon Polito (misspelled "John")
- Main article: Transcript:The Siege of the North, Part 1
- Main article: Avatar Extras for Book One: Water
- While fighting in the ocean, some of the waterbenders stop a Fire Nation battleship the same way the shipwreck seen in "The Boy in the Iceberg" was encased.
- The marks on the foreheads of the Northern Water Tribe warriors are the same type of marks Bato gave Aang, Katara, and Sokka in "Bato of the Water Tribe".
- When Yue giggles at Sokka being licked by Appa, she is missing her gloves.
- When Iroh is talking with Zhao on the boat, the pin on his cloak is a gold and red emblem of the Fire Nation, but in the next episode, the pin is black and red on the same cloak.
- Zuko's injuries have not healed at all since "The Waterbending Master", despite the fact that several weeks have passed since he sustained them.
- After Arnook tells the rest of the tribe about the arrival of the Fire Nation, Yue's betrothal necklace is not around her neck. The necklace appears when she looks at Sokka receiving his warrior marks, but after Sokka looks back at her, the necklace is gone again.
- While Chief Arnook is talking about the impending attack, Yue is sitting on her knees, but in the next shot, she is sitting in an Indian-style position.
- Chief Arnook places three fingers in the cup of red coating at once to give the warrior marks, as demonstrated with the first volunteer. Afterward, however, only two of his fingertips are seen to be red and Sokka and the other volunteers are first given two marks, followed by the third.
- When Sokka looks back at Yue after receiving his warrior marks, the marks are gone. After closing up on Yue's face, the marks are back on his forehead. Also, after the second fireball, when Sokka is searching for Katara, who is under the snow, his warrior marks have disappeared again.
- While riding on Appa, Aang's glider is on the flying bison's neck, but in the next scene, Aang is holding it.
- When Aang jumps off Appa to attack the Fire Navy ships, his staff momentarily turns orange.
- When the camera pans up to show the full armada, a different design is on the flag atop the ship Aang stopped.
- When Katara goes to comfort Aang after his battle with the Fire Navy, her braid is missing.
- When Sokka attacks Hahn, he has front bangs for one scene.
- When Katara and Yue glare at Momo for fishing in the Spirit Oasis, most of Momo's colors are reversed: his back is black, while his belly is white.
- When Katara and Yue are talking while Aang meditates, the bottom of their outfits become gray.
- When Katara tells Yue that Aang is crossing into the Spirit World, her necklace's carving disappears.
- When Katara declares herself capable of protecting Aang, the part of her necklace that connects the pendant to the choker is blue instead of yellow.
- When Zhao watches the sun rise, his hair is gray in one shot but turns brown again in the next.
- When Katara wakes up from being knocked out by Zuko, the part of her necklace that connects the pendant to the choker is the same color as the pendant.
- The commentary involving Sangok's performance and a sea sponge is a subtle reference to SpongeBob SquarePants, another Nickelodeon cartoon, while in the German translation, Pakku refers to a starfish. This is also a reference to the cartoon, as SpongeBob's best friend is a starfish.
- An old Nickelodeon website referred to this episode as "The Northern Water Tribe", but it went on to call the next episode by its working title, "The Siege of the North, Part 2".
- When Arnook says some faces will disappear from the tribe forever, close-ups were shown of Yue, Pakku, and Hahn; all three did disappear from the tribe. Yue sacrificed her life to revive the Moon Spirit, Hahn unintentionally threw himself overboard after Zhao stepped out of the way when he tried to kill him, and Pakku left for the Southern Water Tribe, where he reunited with Kanna and married her instead of returning to the Northern Water Tribe.
- In the dialogue between Hahn and Sokka, Hahn pronounces Sokka's name incorrectly by elongating the "O", which is the Asian pronunciation and how it is pronounced in the film, The Last Airbender.
- This two part episode is Michael Dante DiMartino's favorite episode, as he described it as an awesome way to end the first book.
- When talking about asking the spirits for help, Aang jokingly suggests that the spirits will "unleash a crazy amazing spirit attack on the Fire Nation". This is exactly what ends the siege in the second part, as the Ocean Spirit devastates the Fire Navy through a spiritual link-up with Aang.
- During a brief part where Sokka is marked to join the mission, an instrumental version of Iroh's song, "Four Seasons", plays in the background.