After the Makishima case, Shinya Kougami is fleeing, Nobuchika Ginoza could be seen as a criminal, and two Enforcers have left. This leaves the Public Safety Bureau in desperate need of new personnel. Enter seventeen-year-old Inspector-in-training, Mika Shimotsuki, who joins Division 01 led by Akane Tsunemori.
While Tsunemori has doubts about the Sibyl System, Shimotsuki firmly supports its judgment. However, her first task challenges her beliefs. A new criminal has emerged with the power to lower someone's Psycho-Pass so they are not identified as lawbreakers or even as humans by the System.
When a culprit with irrefutable evidence against them avoids retribution, despite having clear Psycho-Pass readings, swift action is necessary. Inspectors and Enforcers must work together to decipher a menacing message and track down the offender, who is perceived as non-existent by the System.