Yoon Kyung-ho

To make it out of the music room and onto the roof, the students put into action their most perilous plan yet. Elsewhere, Jae-ik comes across a setback.

In need of a cellphone, two students take a risky journey to the teachers’ office. Byeong-chan passes on critical information to Detective Song Jae-ik.

The infected multiply in droves. Scrambling for their lives, Nam On-jo and Lee Cheong-san find safety with others inside a classroom — but not for long.

Inside Lee Byeong-chan’s science lab, a student incurs a seemingly harmless bite. Shortly after, a fast-spreading outbreak soaks the school in blood.

Yeo-jin collects evidence as Si-mok interrogates the suspect. Many questions get answered, but the most important problem of all remains to be solved.

Returning home from the rooftop party, Si-mok discovers that an intruder has left something in his bedroom. Yeo-jin and Geon come over right away.

Si-mok selects key lawyers and police officers to be part of the special investigations team. Their probe begins with Dong-jae as the starting point.

New pieces of evidence only increase the list of possible suspects. In the midst of the confusion, a few begin to question Si-mok’s innocence.

Si-mok, puzzled by the details of the most recent murder case, visits the victim’s home to seek more clues. Yeo-jin joins him in the investigation.

A suspect caught by the witness appeals for unfairness and commits suicide. After his death, Lieutenant Lieutenant Police in charge of discovering evidence that the suspect is not the criminal….

The western part of the prosecutor’s office has been contacted by Park Moo-sung, who was the sponsor of his colleagues’ testimony, to inform him of the corruption of the prosecutors….