Jung Yonghwa is the leader of CNBlue.  He is handsome, a talented musician, a noted actor and a ladies man. He's had his share of scandals most of which he denies. He had been receiving death threats for the last 6 months - the last one was too close for his agency FNC to ignore.

Seo Hyun was assigned by her Uncle's security agency to be part of his bodyguards. They needed a female bodyguard because of the women who constantly swarmed around him.

They disliked each other on sight.