- Drama: IRIS
- Revised Romanization: Airiseu
- Hangul: 아이리스
- Director: Yang Yun-Ho, Kim Kyu-Tae
- Writer: Kim Hyun-Joon, Jo Kyu-Won, Kim Jae-Eun
- Producer: Jung Tae-Won, Choi Ji-Young
- Network: KBS2
- Episodes: 20
- Release Date: October 14 – December 17, 2009
- Runtime: Wednesday & Thursdays 21:55
- Language: Korean
- Country: South Korea
Two elite National Security System (NSS) agents, Hyeong-Jun (Lee Byung-Hun) and Sa-Woo (Jeong Jun-Ho), who were sworn blood brothers, both fall for fellow agent Seung-Hee (Kim Tae-Hee). Sa-Woo attempts to suppress his feelings for Seung-Hee and wishes the couple the best.
Hyeon-Jun is then sent off on a solo mission to Hungary. In Hungary, Hyeon-jun accomplishes his mission and while in escape mode becomes wounded. Shortly later, Hyeon-jun finds out that he was betrayed by fellow agent Sa-woo. Seung-Hee attempts to help Hyeon-Jun escape, but a car explosion separates the two and both are misled to believe that the other person are dead. Hyeon-Jun is then saved by an unknown voice and learns of the secret society “IRIS”.
One year later, Hyeon-Jun returns to Korea to seek revenge. During this time, the two Koreas are set to reunify, while the group “IRIS” are intent on stopping the reunification.