This episode will set you on an emotional ride as viewers get to see what Appa has been up to for the past four weeks in which he had been separated from Aang. The episode begins with the saddening moment where Appa is stolen from the gang by Sandbenders at the Library. While viewers undoubtedly know that a lot of time has passed since Appa's disappearance, and that Aang's attitude has been severely altered, they do not yet know of Appa's pain until watching this chapter unfold.
Facing many adversities, Appa struggles through his imprisonment, going from being captured by sandbenders to being traded away again and again. Viewers are emotionally downcast while watching Appa being abused by the circus, but relieved when Appa pulls off an escape. No doubt Brian Konietzko and Michael DiMartino (B&M) have pulled off a brilliant story line when they can get you so immersed into the happenings of a secondary character such as Appa.
Speaking of which, Appa's escape isn't the end of his troubles. Brilliantly, B&M orchestrate Appa's continuous struggles without Aang by ruffing Appa up with fights and endless travels throughout the night. I, personally, was very sad when Appa had to fight the porcupine/hog-thing and recall asking myself "Man, when is Appa going to catch a break?" Once again, viewers go on an emotional roller coaster when they see the how Appa has lost his trust in even his allies (the Kyoshi warriors -- who are incorporated into a brilliant battle scene that sets up for chapters ahead).
Throughout this chapter, viewers get a chance to see Appa when he was but a baby being tended to by his mother, as well as becoming a life long friend of Aang. Soon after escaping from the ensuing battle between the Kyoshi Warriors and Azula's gang, Appa returns towards his previous home, an Air Temple, where once again viewers are treated to a flashback from the past. There, Appa will meet a future acquaintance of Aang's, who turns Appa in the direction of Ba Sing Se.
Just when you think the roller coaster ride is over, Appa arrives in Ba Sing Se and is once again up for trouble when Long Feng captures and imprisons Appa. Poor Aang didn't know how close he got to being reunited with Appa then and there.
Overall, a masterpiece when it comes to showing viewers how brilliantly B&M can intertwine chapters and story lines. Credit also goes, of course, to the excellent staff that manages the show. This is definitely one of the most emotional episodes viewers are liable to watch, and is an example of the genius B&M have bestowed upon the world in the form of this ceaselessly addicting plot.
Deep plots and characters, effective apposition, powerful emotions: Probably the holy trinity of 'Avatar' episodes. As such, Appa's journey is an amalgam of so many different things that are unrelated, but tied together by Appa himself. Not only do we learn a great deal about a main character who hasn't really been given much character, so to speak, but we also have hints and jabs at many past and possible future events, as well as relations to the present.
The episode cuts across the timeline of the show and follows Appa's journey starting from the events of 'The Library', when he got kidnapped. The rest of Appa's journey is really a number of different encounters that each significantly shapes or expands the plot. But we also get a look into the past through Appa's flashbacks as a young sky bison. Though not crucial to the story, these flashbacks nevertheless help to define the strong bond between Appa and Aang, and tell a little about Air Nomads in general. Plus they are very heartwarming.
One interesting aspect of this episode is the mix of old and new locations and characters appearing in this episode. This allows the viewer to connect to the journey by revisiting known places and seeing known characters and creates a sense of continuity, but it also gives a sense of pushing forward the plot by introducing new things. And since Appa never stays very long at any single spot, these new faces and locations are really just devices for foreshadowing the plot. The places that are shown in more detail then also bear great significance, such as Appa's meeting with the Kyoshi warriors or Guru Pathik.
Indeed, the Guru is probably the most vital piece in this episode. Not only does he give Appa his hope back, and tells him where Aang is, but he hints at meeting the Avatar again in the future. And anything that is important to Aang is important for the show.
In the end, however, this is a chapter about a journey, about moving along. As such, the individual encounters never get resolved. We don't know what happened to the kid in the circus, how the fight between Azula's gang and the Kyoshi warriors turned out, and what exactly the Guru wants with Aang.
This episode's ending is built up very nicely. We get to see Ba Sing Se at night, with Appa flying around trying to find Aang. Then we hear the bison whistle, but, and this is a very nice effect, we see that Aang is asleep. And indeed, the very end is one of an unhappy conclusion: Long Feng has tricked Appa and taken him prisoner, after all the trouble Appa went through.
Overall, this episode runs on a different note than others. This is mostly due to the limited communication, since Appa can't talk, but it is also something akin to a long recap that shows the events of the last few episodes from Appa's point of view. And while there are many unanswered questions left, it is still an engaging and emotionally powerful chapter.