In a smart model city that claims to have "zero crime rate," everything is under the control of data. There is no real night here, because every corner is closely watched by the "guardian" of the AI surveillance system. However, on a carnival night celebrating the upgrade of the city's surveillance system, a never-before-seen murder scene suddenly appeared on the holographic projection, completely tearing apart the perfect disguise of this "Silent City". All the evidence in this seemingly "impossible" murder points to a "ghost" that has long been forgotten by society and even erased from digital identity.
