Avatar: The Last Airbender deals primarily with subjects such as loss, grief, and justice. However, it’s easy to forget that Aang, Katara, and Sokka are just children. Throughout the series, they witness some of the most heartbreaking and disturbing events.
While Avatar: The Last Airbender has lighthearted and funny moments, as Aang has an optimistic and cheerful spirit, it also contains some of the darkest episodes in anime. Avatar: The Last Airbender perfectly balances heartwarming moments with unsettling and frightening scenes.
10 “The Southern Air Temple”
Book One, Episode 3
“The Southern Air Temple” shows Aang’s joyful past through flashbacks as he discovers that his entire community was murdered by the Fire Nation. Aang tells his friends about Monk Gyatso, for example, his good-hearted mentor and close friend.
In the end, Aang sees Gyatso’s skeleton and his grief and anger trigger his Avatar state until Katara manages to calm him down. Aang is only 12-years-old and he must accept the fact that he now lives in a world where his community, and all of his loved ones are now gone.
9 “The Swamp”
Book Two, Episode 4
After Aang, Sokka, and Katara get lost and separated in a swamp, each one of them starts getting unique visions. Aang only sees a giggling girl, but Sokka and Katara have heartbreaking visions about people they lost, which makes the episode truly haunting.
Katara has a vision of her dead mother, but when she happily runs to meet her, the vision disappears, leaving Katara completely devastated. Meanwhile, Sokka sees Princess Yue, who blames him for not saving her, which is an obvious representation of Sokka’s guilt about the situation. Though it turns out the swamp isn’t evil, the episode is still thoroughly devastating.
8 “The Library”
Book Two, Episode 10
“The Library” is both a disturbing and sad episode. Even though it starts with a light-hearted tone, with the team going on vacation, it quickly changes when they enter a legendary library in the desert. There they meet the Knowledge Spirit, Wan Shi Tong, who is weary of humans since they only use knowledge to cause harm to others.
While Aang and his friends promise they will not use their knowledge for violence, they end up finding information that will help them defeat the Fire Nation. Wan Shi Tong discovers this, tries to kill them, and sinks the library. “The Library” is an eerie episode that explores the limits of knowledge with a compelling and morally ambiguous antagonist. On top of that, Toph has to make the difficult decision to allow Appa to be kidnaped to save her friends, one of the most tragic and distressing moments in The Last Airbender.
7 “The Desert”
Book Two, Episode 11
“The Desert” showcases the extent of Aang’s power and the deep bond between Aang and Appa, one of the best pets in cartoons. When Aang and his friends are lost in the desert after Appa is stolen by sandbenders, Aang struggles to control his grief and his raw power.
When the crew finds a buzzard wasp that kidnaps Momo, Aang follows it, rescues Momo, and kills the buzzard wasp out of revenge. After hearing that the sandbenders put a muzzle on Appa, Aang loses all control, breaks the sand-sailers, and almost kills everyone – he’s only stopped by Katara. “The Desert” shows how cruel, vengeful, and bloodthirsty Aang could become if he didn’t have a support group.
6 “The Southern Raiders”
Book Three, Episode 16
Katara has the potential to become one of the darkest characters in animation as she lost her family and community under the Fire Nation’s ruthless rule. “The Southern Raiders” explores Katara’s grief and need for revenge.
Against Aang and Sokka’s wishes, Katara and Zuko embark on a journey to kill Yon Rha, the man who coldly murdered Katara’s mother. Throughout “The Southern Raiders,” there are flashbacks of the day Katara lost her mother as a kid, which is completely heartbreaking. Throughout “The Southern Raiders,” the audience gets to see Katara’s darker side, even if Katara chooses forgiveness in the end.
5 “The Siege of the North, Part 2”
Book One / Episode 20
The last episode of Book One takes a dark turn. “The Siege of the North, Part 2” is an eventful episode where Aang goes to the Spirit Realm looking for the Moon and Ocean Spirits. Here, Aang meets with Koh, also known as the face stealer. To meet with him, Aang has to make sure not to show any emotion, or his face will be stolen by this insect-like creature that wears all the faces it has stolen.
At the same time, Zhao is plotting to steal the Moon Spirit. Zhao initially puts it in a bag, but later kills it, in one of the most shocking scenes in the series. In a tragic turn of events, Princess Yue nobly sacrifices herself to bring the Moon Spirit back.
4 “Lake Laogai”
Book Two, Episode 17
“Lake Laogai” centers around the Dai Li, the police at Ba Sing Se. They’re led by the ruthless Long Feng, who has been controlling the town for a long time. The scariest part of this episode is that the Dai Li have been brainwashing women to become pliable and accommodating and keep control of the population.
“Lake Laogai” features one of the most disturbing deaths in The Last Airbender. When Aang and his friends are looking for Appa, they encounter Jet brainwashed by the Dai Li. A battle ensues in Lake Laogai that ends with Jet being wounded by Long Fen. Even though Katara tries to heal him, it seems that he’s too far gone for any kind of cure. He insists that Aang, Sokka, and Katara leave, but he dies sometime afterward.
3 “The Crossroads of Destiny”
Book Two, Episode 20
Book Two of Avatar: The Last Airbender delivers an outstanding season finale. In “The Crossroads of Destiny,” Azula manipulates the Dai Li to work with her and tries to take control of Ba Sing Se. In the process, she imprisons Zuko and Katara, so Aang and Iroh will have to work together to rescue them.
After an intense battle, Azula surprisingly manages to fatally wound Aang. Even though Katara heals him, the ordeal leaves the path open for Azula to take control over Ba Sing Se, one of the few communities that wasn’t affected by the Fire Nation.
2 “Sozin’s Comet, Part 4: Avatar Aang”
Book Three, Episode 21
The Avatar: The Last Airbender’s finale, “Sozin’s Comet, Part 4: Avatar Aang” offers a bittersweet ending. Not only does the audience get to see Aang’s raw Avatar power, which in itself is both inspiring and terrifying, but Katara has an intense and epic fight with Azula that ends with the latter being pushed to the edge.
Azula is one of the most formidable villains in The Last Airbender and her cruelty knows no limits. However, when Katara defeats Azula, she starts yelling and crying desperately with no control over her body. Darkly, this scene shows this once-commanding antagonist reduced to a wretched person, making it impossible for the audience not to sympathize with Azula.
1 “The Puppetmaster”
Book Three, Episode 8
“The Puppetmaster” is one of the most disturbing episodes of Avatar: The Last Airbender. Here, Katara meets an elderly woman member of the Southern Water Tribe, Hama. They bond quickly, and Hama becomes Katara’s mentor, but she’s hiding one dark secret: Hama uses bloodbending.
Through bloodbending, Hama controls people’s bodies against their will. Though Hama learns this to escape her imprisonment decades prior, she’s now using blood bending to kidnap innocent people – and has been for years. Katara is then forced to stop her mentor. Though Hama is arrested, she’s eerily pleased that she is able to pass her wicked ability on through Katara.