Cha Yeon Jin is a high school girl whose outwardly normal existence and reticent character masks her true identity: she is a professional assassin who is seeking vengeance for her mother after watching her killed in front of her eyes. She infiltrates SS1, the secret organization that her mother was connected to, by becoming one of their killers, all the while trying to track down her mother's murderer.

Baek Joong-won once saved the vampire Ehwa from being burned at the stake by his fellow villagers. While attempting to escape together, Joong-won fell off a cliff, and Ehwa gave him her blood to save him from dying. Thus, Joong-won was also transformed into a vampire.In modern-day Seoul, the 350-year-old Joong-won runs a luxurious wine bar in Gangnam District with Ehwa. Though she holds a torch for him, Ehwa can only observe and protect her friend from afar, as he has long closed himself to any new emotion. One day, Joong-won receives a letter from a former lover, a human he had broken up with 20 years ago without telling her the truth about himself. In her letter, the dying woman asks Joong-won to look after her daughter, Ji-woo.After her mother's funeral, Ji-woo finds a photograph her mother treasured very much, and she searches for the man in the photo, her mother's long-lost lover. When she finds Joong-won, she assumes that he is the son of the man in the photo. As Joong-won spends time with Ji-woo, all his emotions which were frozen by time start to melt away, and the two fall in love. Ehwa has difficulty dealing with this turn of events. Meanwhile, a serial killer who sucks blood from his or her victims is on the loose.

The drama is about the assassination attempts on Emperor Jeong Jo's life during the 8 day period when he left the palace for a ceremony to honor his father who was killed by his grandfather.

Park Han Byul and Park Kwang Hyun star in this bubbly drama about a committed couple who realize they might not belong together at all. Jeong-seok and Yeo-kyung have been dating for years. Jeong-seok is uncultured and poor, while Yeo-kyung is polished and rich. They both begin to feel dissatisfied, and then they both meet someone else. Can true love overcome habit? Couple Breaking is a light-hearted four-episode mini about romantic switcheroos.