Chit Sang was an inmate at the Boiling Rock prison in the Fire Nation. He claimed that he was falsely accused of the crime for which he was convicted, and maintained his innocence. He was rebellious in nature, displaying "unruly behavior" according to the prison guards, and was frequently picked on by them. When Sokka and PrinceZuko broke into the prison, they formed an alliance with Chit Sang, and with the help of Suki, they escaped.
In the summer of 100 ASC, Chit Sang was scolded by a guard for not bowing down as he walked by. While Chit Sang attempted to peacefully go back to his cell, the guard deliberately provoked a response by attacking him with a fire whip, forcing him to defend himself using firebending. He was taken to the cooler for breaking the prison rules, which stated firebending was forbidden. While in the cooler, Chit Sang was visited by the warden, who had apparently heard that Chit Sang had tried to use firebending to escape. The warden reminded him that no person had ever escaped from the Boiling Rock, and stated that he would rather jump in the boiling lake than have that record be broken.
Later on, Chit Sang overheard Sokka, Zuko, and Suki hatching an escape attempt. He demanded to get in on it, threatening to expose the plot to the guards. Sokka reluctantly agreed, and the four of them began planning. The plan would involve completely unbolting one of the coolers, and using it as a boat to get across the boiling lake. Chit Sang and Zuko decided to stage a fight with firebending, so Zuko could get inside the cooler.
When the plan came together, Chit Sang showed up at the cooler with his girlfriend and best friend. Sokka, Suki, and Zuko decided to stay behind, on the off chance that an approaching gondola might have Sokka's father on it. Chit Sang and his companions went on; however, luck was not on their side. Frustrated by the heat and slow current, the former prisoner pulled off a piece of the metal siding, intending to use it as a paddle. When he stuck the paddle in the water, some of the superheated lake water splashed his hand, causing him to cry out in pain. This alerted the warden to his escape attempt, and he and his friends were apprehended and re-imprisoned.
Knowing that Chit Sang was not intelligent enough to come up with this plan on his own, the warden had him interrogated to find out who did. After torture by being suspended upside down until the blood rushed to his head, Chit Sang revealed that it was a man disguised as a guard that came up with the plan. When the warden lined up several guards, Chit Sang identified the guard who earlier harassed him, proving his earlier claim under torture that he was not a snitch and also getting revenge at the same time. The warden was willing to believe Chit Sang's lie, seeing the convenience that the guard had put him in the very cooler that he used to escape.
He was later released to the prison courtyard along with all the other inmates when Sokka, Suki, and Hakoda attempted to start a prison riot as a diversion. After Hakoda's efforts to start a fight failed due to inmates' broken spirits, Chit Sang succeeded by simply picking up a smaller prisoner and yelling "Hey! Riot!" Instantly, the prisoners were fired up, both figuratively and literally. Hakoda noted this as impressive.
Amidst the ongoing riot, Chit Sang joined the other escapees as they made their way to the gondola, where he carried a bound and gagged warden as a hostage. Despite a near plunge to the boiling waters below, Chit Sang and the others survived the gondola and escaped the island via Azula's airship which was present upon Azula's visit to the prison. He later joined the Avatar's group at the Western Air Temple.
Chit Sang was a stubborn and selfish man, usually doing things for his own personal gain, even if others advised him against doing this. However, he also showed signs of gratitude and cooperativeness, as well as trustworthiness in the case of him not revealing Sokka and Zuko as impostors even under coercion. His selfishness and stubborn attitude was first revealed when he insisted on trying to escape even after the first plan to escape the Boiling Rock was postponed. Due to Chit Sang's impatience, the plan failed and he was imprisoned once again.
Realizing he was wrong to disregard the advice of Sokka, he decided to help out with the next escape plan, which succeeded due to the cooperation of the team, allowing all five inmates to escape. Although his attitude and selfishness seemed to have changed due to his failure, a shred of selfishness could be seen as still remaining as evidenced by the fact that he decided to leave his best friend and girlfriend out of the next escape plan.
Apparently, Chit Sang had no qualms about staying with Team Avatar, despite being a Fire Nation civilian.
Chit Sang was chronologically the first known firebender with blue eyes and the only one of Fire Nation citizenship to have this eye color. Other known firebenders with blue eyes are of mixed parentage and live in the United Republic.