While flying, Aang and friends are attracted to a mysterious swamp and are separated from one another. They begin to see unique illusions in the swamp: Sokka sees Princess Yue, Katara sees her dead mother, and Aang sees a mysterious giggling girl and a flying boar

Aang and friends stumble upon a town celebrating an Anti-Avatar Day. The villagers blame Avatar Kyoshi, one of Aang's previous incarnations, for killing their leader, Chin the Great. Aang reveals his identity and is arrested for Kyoshi's supposed crimes. Zuko disguises himself as the Blue Spirit to steal food for himself and his uncle

Aang is still searching for an earthbending teacher, but with little success. At an underground earthbending tournament, Team Avatar witnesses a fighter named The Boulder defeat most of the other fighters but then is himself defeated by a young blind girl named "The Blind Bandit", whom Aang recognizes as the girl from his vision in the swamp

While on the way to Omashu, Aang and the group meet a group of carefree traveling bards, who take them through a vast tunnel known as the Cave of Two Lovers. Zuko and Iroh are sheltered by kind villagers after Iroh accidentally drinks tea made of a poisonous plant. Song, a young and compassionate healer, shows Zuko the effects of war from a normal citizen's perspective

Aang and his friends sneak into Omashu to find Bumi, but Sokka fakes a deadly illness to scare off the guards. They meet a resistance movement who tells them that King Bumi surrendered on the day of the invasion. Meanwhile, Princess Azula decides that in order to catch Zuko and Iroh, she needs to stop traveling with the royal procession. Team Avatar helps the city's entire population escape by faking an epidemic of Sokka's invented sickness

Team Avatar is stranded in the desert, without sufficient provisions to make the trek out again now that they no longer have Appa. Elsewhere, Iroh reveals a mysterious association with a secret society when he uses a White Lotus tile as an opening in a match of Pai Sho, his favorite game

Aang begins his earthbending training with Toph, but grows frustrated when he encounters difficulty with earth, the natural opposite of air. Aang's inclination towards agility and evasion puts him at a disadvantage with earthbending, which requires a more direct, resolute form of combat

Aang and his friends are relentlessly chased by Azula, Mai, and Ty Lee, which makes it impossible for the group to stop and sleep. The lack of sleep makes everyone irritable, and fuels a quarrel between Katara and Toph. Toph realizes they are being tracked by means of Appa's shed fur

After leaving his uncle Iroh, Zuko continues his journey through an Earth Kingdom town where a young boy named Lee befriends him. Zuko remembers his childhood, including Azula's chilling and callous behavior towards the death of Iroh's only child Lu Ten and his own perseverance

Sokka decides the group needs some intelligence to defeat the Fire Nation. At an oasis, the group encounters a professor from Ba Sing Se University, who tells them of Wan Shi Tong's library in the Si Wong desert, said to contain a vast collection of knowledge. The professor and the group eventually locate the library nearly buried, but intact inside

Aang reunites with his friends intent on stopping the drill. Though their offer to help is initially refused by the Earth Kingdom general at the Outer Wall, Team Avatar begins finding a way to take down the drill. They determine the best way is to sabotage the drill from the inside

Aang and the rest of the group arrive in Ba Sing Se, determined to find Appa and inform the Earth King about the eclipse. They soon discover that the bureaucracy surrounding the king, enforced by the Dai Li, the "cultural authority" of Ba Sing Se, blocks them from making contact with him

The episode is a set of vignettes about each of the main characters' adventures in Ba Sing Se, providing a glimpse of their personalities and private lives:

• Katara and Toph have a girls' day out in the inner city
• Aang helps a zookeeper build a new zoo outside the wall
• Sokka accidentally ends up in a girls-only poetry club
• Zuko goes out on a date, resisting at first but winds up enjoying himself
• Momo looks through Ba Sing Se for Appa, finding only one of his footprints
• Iroh provides small gestures of kindness to various people in the outer city, before venturing into the country to find a place to mark the birthday of his son, Lu Ten, who was killed in the siege of Ba Sing Se many years previous. Kneeling before a portrait of his son, Iroh tearfully sings "Leaves from the Vine", a folk song about a young soldier returning home

After leaving the desert, the group fortuitously meets Suki and attempts to lead a pregnant woman named Ying, alongside her husband and sister-in-law, through the Serpent's Pass, a dangerous route to the outlands of Ba Sing Se. They are attacked by a Fire Nation ship and narrowly escape

Aang and Sokka reunite with Toph and set out to find Katara. Azula has been placed in charge of the Dai Li by Long Feng during the coup. Iroh and Zuko are greeted at the palace by Azula and the Dai Li. Iroh evades capture, but Zuko is quickly overwhelmed and thrown in prison with Katara. Iroh finds Toph and Team Avatar joins forces with him

The group breaks into the Earth King's palace to warn Earth King Kuei about the war. They eventually convince the King by showing him the destroyed Fire Nation drill, resulting in Long Feng seemingly being arrested for treason. Meanwhile, Zuko fights an illness which Iroh believes is a manifestation of the deep internal conflict within himself after setting Appa free

As the group searches for Appa, they run into Jet, who falsely claims that he has information on Appa's whereabouts. A chance encounter with Jet's remaining Freedom Fighters, Smellerbee and Longshot, reveals to Team Avatar that Jet had been arrested by the Dai Li a few weeks ago

Aang travels to the Eastern Air Temple and meets Guru Pathik, who trains him to master the Avatar State through the unlocking of his seven chakras, a process which must be completed without interruption

After being abducted in the desert, Appa is traded to a Fire Nation circus, where the trainer whips, humiliates, and generally mistreats him. He eventually escapes with the help of a small boy. He later unwillingly fights a Boarcupine; he wins but is badly wounded