Lee Hyun (Seo In Guk) has shown a high IQ far beyond that of ordinary people since he was a child, but he also showed a devilish side. Therefore, his father Lee Jong Min (Jeon Kwang Ryul), a criminal psychology expert, regarded him as a freak and strictly disciplined him. Unfortunately, Lee Jong Min was killed by a murderer. Lee Hyun, who witnessed all this, lost his memory because of great stimulation. As an adult, Lee Hyun became a professor of criminal psychology and published many books. One day, at the scene of the crime, Lee Hyun met rookie detective Cha Ji-an (Jang Nara). Cha Ji-an was a fan of Lee Hyun's books and was fascinated by this genius author. However, when she wanted to seek help from Lee Hyun, she was coldly rejected by the latter. Cha Ji-an was very interested in the murder of Lee Jong Min and had been persevering in seeking the truth. Fate closely linked Lee Hyun and Cha Ji-an together, colliding with a wonderful story.