Isogai Shirou, a loose cannon from the Community Safety Division of the police force, teams up with Kuroi Hinata, a young girl with a sixth sense for finding serial killers. Together, the two seek revenge for their lost loved ones—Isogai’s fiancée and Hinata’s sister.

However, they have to be careful, since they've got even more than vicious murderers to worry about. Isogai’s fellow officers don’t condone vigilante justice, so they hire a criminal psychologist to track down the mystery informant who’s been solving cases for the police. Every second spent evading his own people is time killers could use to escape. The clock is ticking!