Kya, Aang, and Sokka were all fleeing from Zuko, who was aboard his ship in pursuit of them. The gang encountered a sea serpent, but rather than attacking them, it diverted its attention toward Zuko's ship, allowing them to escape to an island. There, Sokka, annoyed by their "goofing off", went off to find food alone; he found some wild berries later that were of bad taste. As he turned away from the bush of berries, Fire Nation soldiers ambushed him and took him captive.
At the Fire Nation base, when brought to Zuko, Sokka refused to back down and insulted him to his face, calling him "scar boy". Shortly thereafter, Kya was brought in as well, but the two refused to tell Zuko of Aang's whereabouts. Moments later, Aang flew in, shocking everyone; the soldiers threw Sokka and Kya into a pit. There, Sokka tied a forked stick to some rope and threw it upwards, hoping it would catch something, but failed and he found the situation hopeless. When Kya tried to bend some water that was dripping into their pit, Sokka harangued her, seeing no point in it. However, Kya succeeded in getting them out.
When they were surrounded by soldiers, Sokka tied his boomerang to a piece of rope and threw it to Aang, who was flying by them. It managed to hold onto the end of Aang's glider. Sokka grabbed hold of Kya while Aang led them out of the base. In the process of escaping, Sokka accidentally managed to find food.
Sokka was revealed to have been designed as a more serious character than he eventually became. However, he still seemed to have been designated as a comic relief character, as evidenced by the scene with the wild berries and his capture. In the Avatar Nick Mag Presents: First Edition issue by co-creators Michael Dante DiMartino and Bryan Konietzko, the creators admitted that comedian voice actor Jack DeSena's lively dialogue, capped off by his improvisation act in the pilot episode, encouraged them to make Sokka a more important and comical character.