The show follows Aang (Zach Tyler Eisen), the last airbender and the “Avatar”, on his journey to bring balance to a war-torn world by mastering all four elements: air, water, earth, and fire.

On his quest, he is joined by companions Katara (Mae Whitman), Sokka (Jack DeSena), and Toph Beifong (Jessie Flower), and hunted down by Fire Nation prince Zuko (Dante Basco) and princess Azula (Grey DeLisle).

The first part, written by series co-creator Michael Dante DiMartino and Joshua Hamilton, and directed by Ethan Spaulding, follows Aang and his friends leading a family, including a pregnant woman, through the dangerous "Serpent's Pass" while on their way to the Earth Kingdom capital city Ba Sing Se, while Zuko joins a group of freedom fighters aboard a ship also heading to the city.

The second part, written by Bryan Konietzko and directed by Giancarlo Volpe, follows Aang and his friends as they try to stop a giant drill, led by Azula, from breaking through Ba Sing Se's inner wall.

Meanwhile, Zuko and Iroh meet a band of freedom fighters on the ferry to Ba Sing Se, consisting of Jet, Smellerbee and Longshot.

The next day, the group find a gap in the Serpent's Pass forcing Katara to split the water and create a path for them to travel on.

Just as she reaches the halfway point, the serpent destroys the ice bridge leading to Toph falling in water and calling for Sokka to help her.

Aang flies ahead and glides to the top of the Ba Sing Se wall where he sees a Fire Nation drill approaching.

Aang meets with General Sung who insists the Avatar's help is unneeded as he has already sent a group of earthbenders - known as the "Terra Team" - to stop the drill.

The Terra Team are quickly defeated by Ty Lee's chi-blocking leading to Aang and his friends deciding to take action themselves.

As Azula is about to kill Aang, Sung sends a barrage of boulders flying towards the surface of the drill which just breaks through the outer wall.

Main cast members Zach Tyler Eisen, Mae Whitman, Jack DeSena, Jessie Flower, Dante Basco and Dee Bradley Baker appear in both episodes as the voices of Aang, Katara, Sokka, Toph Beifong, Zuko, and Momo respectively.

Appearing as guest stars in "The Serpent's Pass" are Mako as Zuko's uncle Iroh, Crawford Wilson as Freedom Fighter Jet, Nika Futterman as Smellerbee, Jennie Kwan as Suki, Brian Tochi as Tran, Kim Mai Guest as Ying, Karen Maruyama as bureaucrat, and James Sie as the cabbage merchant in his penultimate appearance in the show.

[e] Appearing as guest stars in "The Drill" are Mako, Grey DeLisle as Fire Nation princess Azula, Cricket Leigh as Mai, Olivia Hack as Ty Lee, Wilson, Futterman, Barry Dennen as General Sung, Kristoffer Tabori as a Fire Nation war minister, and Guest.

"[6] In 2020, The Harvard Crimson ranked "The Serpent's Pass" and "The Drill" as the 24th and the 17th best episodes of the series respectively praising both Azula's scare factor as a villain and the character moments regarding Aang, and Sokka and Suki.