Ha Woo-Shin and Song Soo-Hyun are twin brothers. Woo-Shin is a best-selling, mystery novelist and Soo-Hyun is a prosecutor at the Central District Prosecutors' Office. 22 years ago, when they were children, their step-father was killed. Now, they discover that their birth father is the person that killed their step-father and he received the death sentence. They soon learn that their birth father was framed for their step-father's murder and they chase after truth.