Sou is a detective for the New York Police Department. Losing his father in a murder as a little boy drove Sou to go to the United States to become a detective. In Tokyo, Maruo partners Sou, whom he met in NY when he was assisting a drug cartel case. Maruo is a compassionate, special investigations detective, but he is actually a former motorcycle gang member. At the crime scene, where the two meet, they find a woman named Yuki just standing there. Although the two speculate that Yuki knows exactly what had happened there, it turns out that she had lost her memory.