Aang, Katara, and Sokka arrive at an Earth Kingdom mining village to find that it is under the control of the Fire Nation. There they meet Haru, a young earthbender who has to keep his bending skills a secret because of the Fire Nation's oppressive rule. Anyone caught earthbending is taken away immediately, which is what happened to Haru's father 5 years ago. During a walk, Katara and Haru come across an old man being crushed by a collapsed mine. They try to help him escape, but the only way they can succeed is if Haru uses his earthbending. After some coaxing from Katara, Haru does and they help the man to safety. But the old man rats Haru out, and during the middle of the night firebenders come to take Haru away. Feeling responsible for Haru's arrest, Katara gets herself arrested in an attempt to track down and rescue Haru. Aang and Sokka follow her to an offshore prison rig where the enslaved earthbenders are held captive and extremely demoralized. Katara tries to inspire them to fight back, but to little avail. She doesn't give up though, and with some help from Aang and Sokka they manage to help the earthbenders help themselves. A battle breaks out between the earthbenders and the firebenders on the rig, and the earthbenders win. They escape on the ships and head back to shore to reclaim their village, while Katara, Aang, and Sokka continue on their way to the North Pole.
You can find a full transcript of this episode at AvatarSpirit.net