A car explosion puts Pei Su’s life at risk. The SID closes in on a shadowy figure.

The suspect's alias and tragic past come to light. Luo Weizhao takes a more personal approach to uncover the truth.

A new case involving a missing girl echoes a cold case from 16 years ago. Luo Weizhao revisits the father of a past victim for leads.

A girl vanishes during Pei Su’s birthday dinner. The team connects her disappearance to a survivor of a similar past case.

Clues lead to a chilling diary found with human remains. A twisted relationship and dark secrets emerge.

The investigation uncovers new truths about a cold case, and two new interns, including Pei Su, join the SID

A series of deaths and a fire point to a larger conspiracy. Pei Su and Luo Weizhao uncover secrets buried in Pei’s childhood home.

Luo receives a cryptic letter from his late mentor. A new case begins as five students disappear.

A mutilated body is found. Surveillance footage identifies a long-wanted criminal from the "327 Case".

Trust is tested as Pei Su speculates he might be the "Purifier". Luo Weizhao affirms his belief in Pei.

The team traces surveillance footage to uncover the criminal’s hideout.

A drone-supported raid leads to the discovery of a planted bomb — an ominous escalation.

Old injustices resurface. Luo Weizhao uncovers secrets tied to the notorious Seine Riverside case.

The team discovers the star witness was impersonated. The SID suspects an internal leak.

Pei Su delves into his subconscious for answers, learning the identity of a missing professor.

A bug is found on an SID member. Pei Su and others suspect a high-level traitor.

A raid on a nightclub uncovers new evidence. A crucial clue from a surveillance camera refocuses the investigation.

A corporate heir is kidnapped. Family secrets and power struggles within the Zhou Group surface.

A shocking package from the past revives questions about a suspicious death. The SID follows new leads.

A student reveals a hidden hierarchy of abuse within a boarding school.

Interrogation reveals manipulation and cover-ups. A victim tried to expose systemic violence before his death.

A repressed memory reveals a key player in past cases. A shocking disappearance changes the game.

As suspects flee, more details about the Zhou Group’s shady rise to power are exposed.

Pei Su recovers in the hospital and begins to trust Luo. A mysterious visitor brings insight into Pei’s past.

All forces converge at an abandoned mansion — the site of a past murder. Loyalties are tested.