Ty Lee was a cheerful and energetic teenage girl, hailing from the Fire Nation. The daughter of a nobleman, she attended the Royal Fire Academy for Girls with her longtime friends, Princess Azula and Mai. As a child, she dealt with six sisters that shared an identical appearance to her, which caused Ty Lee to feel a loss of individuality, a longing to be a distinct, recognizable person, and a desire for attention from other people. Because of this, after she matured, she ran away from her home and joined a Fire Nation circus, becoming a skilled acrobatic performer and gaining more personal attention.
Ty Lee was a formidable hand-to-hand combatant, utilizing a unique form of martial arts that attacks the pressure points on the human body. By striking these, she was able to disrupt that individual's chi flow and temporarily paralyze them, removing their ability to use bending. She and Mai were recruited by Princess Azula to hunt down and capture her relatives Prince Zuko and Iroh, and later, the Avatar and his friends.
Mai later betrayed Azula to save Zuko's life, which led to an attack from the infuriated princess. Ty Lee rescued Mai from injury, or even death, by paralyzing Azula, which led to her and Mai's imprisonment. While in prison, she was reunited with the Kyoshi Warriors and befriended them. In return for teaching them how to block chi, she joined their group and was released from prison when the War ended, ironically adopting their makeup, effectively becoming one of a matched set.