"The time to fight back is now! I can tell you the Avatar has returned! So remember your courage earthbenders, let us fight for our freedom!"
— Katara giving a speech to hopeless imprisoned earthbenders.
Aang, Katara, and Sokka camp near a small Earth Kingdom town controlled by the Fire Nation, where earthbending is forbidden. Katara convinces a young earthbender named Haru to save an old man using his bending abilities, for which he is consequently imprisoned. In response, Katara devises a plan to have herself arrested to free him. While in the prison, she incites a rebellion and the inspired prisoners liberate themselves. Afterward, she realizes she has lost her mother's necklace; left at the prison, it is discovered and taken by a pursuing Zuko.
Team Avatar is setting up camp when Sokka arrives with dinner, which turns out to merely be some nuts. While discussing their dinner options by their campsite, Aang, Katara, and Sokka are startled by loud noises in the distance. Curious, Aang and Katara set out to investigate with a wary Sokka following close behind, and they discover a young earthbender practicing his bending. Katara introduces herself, but the young bender races off fearfully. Aang suggests following him in hopes of finding a town where they can have a proper dinner, and they end up in a small settlement swarming with Fire Nationsoldiers.
They find the same young man and follow him into a store. They see him speaking with his mother and inquire as to why he fled earlier. The young man, Haru, and his mother explain that since the Fire Nation took control of the town, anyone discovered to be an earthbender is arrested and sent to a prison rig, far offshore. Haru's mother subsequently tells them that his father was one of those sent to the rig.
Later that day, Haru and Katara take a walk together, both sharing their own stories and seemingly forming a strong bond. They come across an old man that has been trapped by a cave-in; Haru reluctantly uses his earthbending to save the old man. During the night while the gang is sleeping, Fire Nation soldiers, along with the old man whom Haru had saved, come and arrest Haru for earthbending. The next morning, Katara encounters Haru's mother, who tells her that Haru was arrested and sent to the prison rig because the old man turned him in to the Fire Nation. After hearing this, she decides to take action and find a way onto the rig in order to free him. She concludes that the only way is to trick the Fire Nation into thinking she is an earthbender. After some strategy, she is able to pose as an earthbender, with the help of Aang and some ventilation pipes, while Fire Nation soldiers are watching. She is promptly apprehended and sent to the rig. There, she and several other captives meet the prison warden, a self-important and cruel taskmaster. He states that the earthbenders are helpless since the entire rig is made of metal and thus have nothing to control.
After finding Haru and his father, Tyro, Katara inquires as to how they plan to escape. Tyro says that escape is not an option and the only way to survive is to do what they are told and hope the Hundred Year War goes in their favor. Shocked by his lack of hope, Katara delivers an inspirational speech in an attempt to lift the spirits of the other benders, but they ignore her. That night, Katara meets up with Aang and Sokka to devise a way for the prisoners to regain their confidence and rebel. Aang notices the smokestacks in the distance and states that they are burning coal, meaning there is earth on the rig for the prisoners to bend.
Drawing from their previous idea of feigned earthbending, Sokka has Aang close all the vents in the vicinity where the coal is being burned, save for one that leads to the outer vent where Katara and Sokka are. The warden discovers them and threatens that they are to surrender or die. At that moment, however, coal bursts from the vent and lands before Haru and the others. Katara states that this is their chance to stand up and fight, however, no one seems to have the will to revolt. The warden claims that their spirits were broken long before the young waterbender's arrival and walks away in triumph.
As he departs, a chunk of coal strikes him on the back of the head. He turns to see that the one responsible is Haru, who bears a look of rage on his face. The warden attacks Haru, but his assault is blocked by Tyro and two other benders. The prisoners begin to regain their hope and join in battling the Fire Nation soldiers, eventually emerging victorious after a dramatic struggle. With the help of Team Avatar, they throw the warden overboard and sail away in stolen Fire Nation ships. Tyro thanks Katara for renewing his people's hope and Haru also expresses his gratitude. Katara is touched by Haru's words, but suddenly notices, to her distress, that her mother's necklace is no longer around her neck.
On the rig, PrinceZuko finds the necklace, its fabric strap torn, on the deck. With a blank look, he takes the necklace in his hands and looks out toward the horizon.
When Momo is trying to crack a nut, he is seen near the edge of a large rock. However, when the screen pans out, he is standing away from the edge near a fallen tree.
When Sokka is warning the rest of the group to approach Haru carefully, Katara's shoulder can be seen in the lower left corner of the screen. However, in the next shot, she is quite a distance from Sokka and Aang and is already greeting Haru.
When Sokka walks over to comfort Katara after Haru's arrest, the glove on his left hand disappears briefly.
Before Katara gets arrested, the camera shot displays the second air vent, but Aang is not there. When the camera view gets closer to the air vent, Aang can be seen sitting by the vent, playing with a butterfly.
As Aang bends air to lift the rock, Momo is standing right behind it. However, after Sokka corrects the Fire Nation soldiers that it is Katara who is bending the rock as opposed to the lemur and the rock descends, Momo can no longer be seen.
In the scene where the prisoners are seen in their encampment for the first time, Katara is second to farthest left in the lineup, but when the warden is shown walking while talking to the prisoners, she is shown farthest left in the line.
When Katara prepares to administer her speech to the earthbenders, she uses a pan lid to draw their attention, but while she is speaking, the pan lid disappears.
When Sokka explains his plan to transport coal to the earthbenders, there are no other people around in the vicinity, as seen by an overhead shot. When he finishes his explanation only moments later, there are still no others present, but in the very next frame they are surrounded by every earthbender prisoner and numerous Fire Nation guards.
When Sokka is breaking the Fire Nation guards' spears, Katara is seen without her necklace, but she is wearing it again while feeding coal into Aang's air funnel before losing it.
When Tyro is thanking Katara for her help, Katara's braid becomes detached from the rest of her hair.
George Takei and his family found themselves in a similar situation to the earthbending prisoners in this episode; during World War II, they were forced to relocate to a Japanese-American internment camp in Arkansas, and later transferred to another camp in California. Much like the villagers who were being imprisoned simply for being earthbenders, Takei and his family were forced into these camps simply for being of Japanese heritage.
This is the first episode in which all four elements are bent outside the opening credits: Haru, Tyro, and the other prisoners earthbending, Katara waterbending, the warden and other Fire Nation soldiers firebending, and Aang airbending.
According to Avatar Extras bonus commentary for this episode, when Aang is asleep the night the Fire Nation troops capture Haru, he is dreaming about Katara with a big smile on his face.
This is the first episode in the first series whose name does not start with the word "The", and one of only two episodes to only consist of one word, the other episode being "Jet".