Ji-eun & Eli are professional jewellers; or to put it simply, they are theives who spent their lives stealing diamonds and other jewelleries. They give most of the money to charities and help needy children; the rest is kept for themselves.Eli wants to find the most precious diamond in the world, the Sukira Diamond. His father, originally a jeweller, was the one who made the diamond. However, Mr Kim got accused of stealing it after his boss lost the diamond. In the end, Mr Kim committed suicide as no one believed he was innocent. Later it was found out that Mr Kims boss was the one who stole it to repay the loan sharks debt because of his gambling habits. Therefore, Eli set his mind out to steal the diamond and claim back what he believed was his fathers.Jieun is Elis partner-in-crime and also, his girlfriend. They met when she found out her boyfriend was cheating on her in the bar. Eli saved her and thus, she sees him as her saviour. From then on, she follows him and helps him along the way.However, Eli only wants the diamond and doesnt want to settle down with a girl. Whenever Ji-eun brings up the topic of marriage, he will shrug it away and says that his job is more important. Will Ji-eun bear with her boyfriends insincerity... or fall in love with another? What makes it worst is Eli is a playboy who uses other girls feelings in order to steal... Ji-eun tries to tell herself not to be jealous as its all part of the job but when she meets another guy... it all changes.Chun-ji is one of the most devoted man on Earth. Not only that, he is good-looking, rich and a true gentle-man. What defeats this purpose is having a twin brother, Chan Hee, who is completely the opposite. Chan Hee is a one of the biggest playboy and cheats on all his girlfriends... Chun-ji always take the blame for Chan Hee as they look exactly the same and gets slapped by countless of girls Chan Hee cheated on. He havent really dated anyone, as everyones afraid of him because of Chan Hee, until he met one... very special girl.