Choi Kang-ta is a super agent with a feared reputation who gains powers similar to a god. As a child, he lost his parents and was adopted by an American couple. After becoming an adult, he returns to Korea to exact revenge on the murderer of his father. He learns that there were four people responsible for his father's death. In the midst of carrying out his plans, his partner Vivian betrays him, putting his life in danger. He is nursed back to health by Bo-bae, a reporter he met by chance, and as he falls in love with her, his beliefs are shaken. After recovering from his wounds, he settles down in a slum neighborhood where he befriends the poor residents. For the first time in his life, he is surrounded by warmth and love in his new home, and finds peace within himself. But Hwang Woo-hyun, a high-ranking official at the Korean Central Intelligence Agency and heir to the Hwanglim Group empire, becomes enraged with jealousy that Choi Kang-ta stole Bo-bae away from him and decides to have him eliminated.
Michael trains himself for revenge against his father's killers. While carrying out his mission to kill Chairman Kang, he runs into Bo-bae, a young, fearless reporter.
Woo-hyeon picks up Bo-bae and tells her that the person meeting with Chairman Kang on the yacht wasn't who they think he is.
When Bo-bae is about to fall off from a horse, both Michael and Woo-hyeon run to save her. Vivian starts to feel jealous of Bo-bae.
Michael anonymously sends a message to Chairman Jang that he is the one who killed Chairman Kang and warns him to watch out.
In accordance to his revenge, Vivian seduces Jang Ho, while Michael approaches Jang Mi. But Michael also cuts off contact with his team to be with Bo-bae
Bo-bae informs Woo-hyeon that she saw Chairman Jang's secretary while she was kidnapped but Woo-hyeon lies to her about the secretary's whereabouts.
Michael threatens Justice Lee to arrest Chairman Jang. Michael and Bo-bae have a bonding moment, which makes Vivian furious.
Woo-hyeon is assured that Peter Pan is Choi Kang-ta who was adopted to the United States 25 years ago.
Out of jealousy, Vivian makes Bo-bae the target of Chairman Jang.
Woo-hyeon fails to catch Michael and is trapped by the bombs he set up.
Woo-hyeon asks Michael if he is willing to cooperate in catching Peter Pan. Vivian overhears a shocking fact between Chairman Jang and Bo-bae's mother.
Triggered by her jealousy, Vivian betrays Peter Pan and reveals his identity.
Michael is shot by Woo-hyeon and is falsely accused in the murder of Justice Lee.
After finding out Woo-hyeon and her own family killed Michael, Jang-mi loses her mind. But Michael, now going as Peter Pan, is not easily rid of.
Peter Pan disguises himself to counter-attack his enemies, and sets Woo-hyeon up in a trap.
Woo-hyeon finds Peter Pan's sister, who was believed to be dead by the fire years ago. Jang Ho proposes to Vivian.
Peter Pan poisons Woo-hyeon, but his plans for revenge go awry with a trap set by his enemies.
Bo-bae finds out the identity of Peter Pan's sister. Peter Pan shows up before Mi-soo.
Woo-hyeon captures Peter Pan and promises his father that he will kill him and Mi-soo together.
Jang Ho finds out about Vivian's true nature as Michael's spy.
Woo-hyeon and Jang Ho use Vivian as bait to catch Peter Pan.
Chairman Jang loses the control and shares of his company to his former partners.
Jang-mi learns the truth from Bo-bae and learns something more shocking in her own house.