There are six main characters, three men and three women. The three women are sisters.
The three young men had a plan to build a company and develop it to be the best. Luck was on their side and everything was going well until one of them decided to drop out and create a new company. He did so because he wanted to build a computer company, and the company they built was going in another direction. His business was going well at first, but it eventually went bankrupt. He visited his two ex-business partners and asked for help, but they refused to help him. He committed suicide, leaving his son, Sin Hoo Kang, without any resources.
The second of the three original business partners had 3 daughters, but he was killed in a car accident.
The last remaining business man who is now a chairman of the largest company in Korea adopted the three daughters and raised them like his own.
More than 10 years passes and Sin Hoo Kang is fully grown and graduates from top-class university in America. He's ready to come back to Korea and execute his plan for revenge.