When three "accidental deaths" occurred in an elite junior high school one after another, the detective discovered the only connection: 24 hours before each incident, a hand-drawn death notice card appeared on the abandoned stairs of the school.
Transfer student Ye Qing begins to suspect her genius classmate Lin Che - he always "happens" to check out specific books before crimes occur. The gentle psychology teacher Su Wan is overly concerned about the past of the victimized students.
The day before graduation, a fourth card appeared, this time depicting a human silhouette of the entire auditorium.
This is a countdown to the ultimate trial on campus.
But the real fifth step is not on the stairs, but in everyone's choice.
Purpose: When justice loses its voice, does "lynching" of using evil to fight evil gain legitimacy? And - how the cycle of violence is secretly transmitted between the injured and the injured.