This drama tells the story of a brother and sister whose father, Takashi, was killed while working as a policeman. Soon after, they learned that the criminal was a cadre of Japan's largest special fraud organization "Phantom Beast", and the two decided to avenge their father. The elder brother Watarase Kiichi was a policeman with a strong sense of justice and action, and the younger sister Watarase Yuki was an engineer at a national university and an excellent white hat hacker. The two used their respective expertise to infiltrate the organization and confront the great evil.