Book 3: Fire
Chapter 5: The Beach
Due to the lack of any real progress made in the storyline, some people may think that the episode gets a little boring. But I see it as necessary progress that really needs to be put somewhere. The episode clearly shows Zuko's transition from being confident with who he is, to realising that even though he has sorted out the Avatar he is still angry and confused. It shows Azula's attempt to fit into a normal life, even though she is clearly crazy. And it shows the reason why Ty Lee and Mai are who they are.
As for the Gaang, they finally meet the Combustion Man,
Anyhow, an average but necessary episode with some funny moments.