Two inspectors are newly assigned to the Public Safety Bureau’s Criminal Investigation Division Unit 1. Arata Shindo, Japanese and Kei Michael Ignatov, East European who has been naturalized in Japan have been friends beyond nationality since their childhood. In the unsolved case over export of the SIBYL Systems and the leakage of technology (in Psyco-Pass Sinners of the System Case.2), Arata’s father committed suicide after he killed Kei’s brother. Since then, they turn out to be the bereaved family members of the offender and victim. Both Arata and Kei become inspectors to look for the truth behind the mysterious case. They deeply trust and care for each other as they team up and lead the rebellious enforces to follow the cases one after another