Contains spoilers for this episode and earlier episodes.
The helicopter passes without rescuing the students, leaving them to plan for a longer stay in the broadcasting room. On-jo recalls her father's survival advice and helps arrange a separate toilet area. Food and water remain a problem, and the group needs a way to contact the outside world. Cheong-san's mother reaches the school grounds, but her attempt to call out to the infected Gyeong-su ends with zombies surrounding and attacking her.
At the police station, Byeong-chan explains how the school's response to Jin-su's bullying pushed him toward trying to change his son. Zombies overrun the station before the interrogation can lead to a solution. Byeong-chan helps detective Jae-ik escape and directs him to a laptop in the school laboratory that holds his research. Across town, So-ju protects the people trapped in the council building and helps them reach its roof, still hoping to return for On-jo.
Su-hyeok and Cheong-san head for the teachers' office to retrieve a phone. Eun-ji has left the roof to destroy the devices connected to the bullies' threatened video, and she continues after being attacked by zombies. The boys become separated during their search. Cheong-san finds Gwi-nam restraining the principal and films the bully killing him. He escapes with the phone, but Gwi-nam follows to destroy the recording and throws a knife at Cheong-san's back.