Detailed InformationBroadcasting company: MBC
Official Website : http://imbc.com/broad/tv/drama/dog/
Genre : Action, Romance
TV Premiere: 2007-Jul-18 to 2007-Sep-06
Production : Scriptwriter: Han Ji Hoon, Yoo Young Jae
Main Casts : Lee Joon Ki as Lee Soo Hyun, Nam Sang Mi as Seo Ji Woo, Jung Kyung Ho as Kang Min Ki.
Running Time per Episode : 60 mins
Total Episodes : 16 Eps
For MBC Wallpaper from this drama : click here
After his mother is brutally murdered in front of him by the Thai Qing Faction's gangster Mao, Lee Soo-hyun (Lee Jun Ki) is adopted into NIS agent Jung-hos family. Together with Min-gi (Jung Kyung Ho), Jung-hos son, Soo-hyun becomes an NIS agent. Soo-hyun met Ji-woo (Nam Sang Mi) when they were about twelve years old and has another fateful encounter with her 13 years later. Together they had promises for the future.
One day, Soo-hyun leaves for an operation dealing with the Cheongbang, only to return in failure because of the resurfacing terrible childhood memories of when he was in Thailand. Due to his thirst for personal revenge and ignoring orders Soo-hyun was fired and stripped of his title as an NIS agent. The chief of NIS agents, Jeong, proposes to the distraught Soo-hyun to infiltrate the Cheongbang. Through Chief Jeongs proposition, Soo-hyun becomes an undercover NIS agent after staging his own death (car accident). Hiding his past, Soo-hyun infiltrates the Cheongbang with revenge in mind, leaving Ji-woo behind. Under the pseudo-name of Kay, he passes through the backstreets of Bangkok. He plans on becoming one of Maos underlings to uncover Maos illegal business. What Soo-hyun didn't know was Ji-woo is the daughter of the same villain, who killed his mother and father.
Meanwhile Min-gi has fallen in love with Ji-woo and she begins to consider his proposal to officially court and forget Soo-hyun. Soo-hyun, now known as Kay, heard that Mao likes Muay Thai (Thailand Boxing aka Kick Boxing), so Kay becomes a Muay Thai athlete, hoping Mao would see him. Mao does come to one Muay Thai game, Kay loses the match but overhears conversation between Cheongbong's Mini Boss trying to kill Mao. When Mao went up to the stage to honor the champion, the assassin aims at him but Kay saves Mao. Mao then took Kay as his right-hand man. Mao and his gang goes to Korea to expand their drug business. They make a company called BS Enterprise. Kay's mission was to protect Ji-Woo from the Korean gang, Spider.
The Spider Boss tries to kidnap Ji-Woo, but little did they know Soo-Hyun was protecting her by following around in his car by Maos orders. When Ji-Woo was rescued by him, she was in lot of shock. He hides her from the Spider Gang by dropping her off behind the container and backs right out of the dead end to engage in a dangerous car chase. Soo-hyun gets shot in the head and loses control, his car then falls into the sea. He wakes up later in a wise old lady's house, but he had lost all of his memories. Later, he gets kidnapped by the spider gang and is used as bait for their trap to get Mao come alone without his Qing Faction gang. Things turn into reversal as Kay kills the Spider Boss and saves Mao once again. Mao now sees Kay as not only his life savior but a son. For the Qing Faction gang, Kays words are Maos orders.
One day, Mao comes to Ji-Woo (his daughter) and she sees Soo-Hyun. She is in shock again. Later, she meets him again but does not believe it is him because of his jerkish attitude. He says that she is selfish. She gets angry and when she gets home, she ripped up a picture she drew of him before.
While he is protecting Mao's girlfriend (she was going shopping), his adopted dad sees him. He looks at him and Soo-Hyun smiles at him then runs away. His dad then tells the Chief of the NIS that Soo-Hyun has amensia. They plan to save him from the gang. While on this mission, the Spider gang's follower (now part of Mao's gang) shoots his dad and his father then subsequently dies. But not before his adopted father called him "Soo-hyun" and said that he wasn't really Kay. This is where Soo-hyun begins to doubt himself as Kay.
The ex-follower of the Spider gang runs away after trying to persuade Kay to go with him. Min-gi arrives at the scene and sees Soo-hyun and his adopted father. Min-gi vows to kill Kay with his own hands.
Over the span of the next episodes, Min-gi and an old ex-NIS agent and restaurant owner form an investigation team secretly with two other NIS employees. Min-gi becomes obsessed with bringing down Kay and Cheongbang (Mao's gang). Ji-woo is convinced that Kay is Soo-hyun.
Lee Soo-hyun (Kay) - Actor Lee Joon-gi
An NIS agent. Underneath his quiet demeanor, he has a violent temper. At a young age, he lost his mother when she was killed by Mao, a Triad gang member. NIS Agent Kang Joong-ho adopted him and raised him with his son Min-ki. After learning that Mao became a Triad boss, he infiltrates the gang as an undercover agent. He assumes a new name, Kay, and goes on a rampage as a gangster to gain the trust of his gang.
Kang Min-ki - Actor Chong Kyung-Ho
An NIS agent. He's a very competitive person behind his easy-going smile. As the son of NIS Chief Agent Kang Joong-ho, he grew up with Soo-hyun like brothers. After becoming an NIS agent like his father who, he admires the most in the world, he gets involved in a love triangle with Soo-hyun and finds himself competing against him at the agency. When Soo-hyun leaves the agency, he confesses his love to Ji-woo and they become lovers.
Seo Ji-woo - Actress Nam Sang-mi
An art director. She has a bright personality and is very considerate to other people. She's honest about her feelings. After meeting her childhood friend Soo-hyun one day, they begin dating. But then Soo-hyun leaves her suddenly. She becomes Min-ki's girlfriend after that and while she was getting over her painful breakup with Soo-hyun, she meets "Kay."