The drama revolves around a guy and a girl, who both experience a painful end to their first loves at the tender age of 15, and then meet again as adults by playing game of love hide and seek.
Han Jung Woo (Park Yoochun) has been a homicide detective for 2 years and he is looking for his childhood love, Lee Se Yeon (Yoon Eun Hye). Lee So Yeon is a fashion designer and often dream of Han Jung Woo searching for her.
Meanwhile, Kang Hyung Joon (Yoo Seung Ho) is a cold-hearted, charismatic fund manager, who tries to take revenge on Han Jung Woo because of the troubled relationship within their family.