In the not-too-distant future, the technology company "Bright Day" has developed a neural implant that can accurately read human moral choices, claiming to be able to eliminate crime and make humans perfect. But in the implant testing team, young engineer Su Che unexpectedly discovered that the device would stimulate the deepest dark impulses of human beings at night and materialize thoughts rated as "immoral." Those phantoms wander in the darkness of the city, inducing people's irresistible desires and fears. After Su Che witnessed a nightmarish violent incident, he began to doubt the real purpose hidden behind the implant. He is both a victim and an operator, and must make a choice between self-salvation and moral decay. When "day" turns into a night that devours humanity, can Su Che uncover the truth, or will he become the monster of his own choice? The boundary between technology and humanity was repeatedly torn apart by blood and lies, and Su Che stepped on the edge of fear with every step he took.
