Kim Hyun Joon and Jin Sa Woo are best friends, who are both secret agent of South Korean agency called the National Security Service. They are both in love with the beautiful colleague Seung Hee, but Seung Hee falls for Hyun Joon so Sa Woo tries to hide his love for her. Huyn Joon and Sa Woo are sent to Hungary for a task, from which, a veil of secret about a war profiteering organization known as IRIS is gradually revealed and leads the two friends to confront each other.