12 episodes · first aired 2022-01-28
| Still | # | Title | Overview | Air date | Rating |
|---|---|---|---|---|---|
 | 01 | Episode 1 2022-01-28 | 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. | 2022-01-28 | 8.3 |
 |
Ratings shown are community scores. Once OMDB is wired, these become per-episode IMDB values.
| 02 |
Episode 2 2022-01-28 |
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. |
| 2022-01-28 |
| 8.4 |
 | 03 | Episode 3 2022-01-28 | When one of the group is scratched while fighting a zombie, Lee Na-yeon demands they kick him out. Outside, the virus swallows up the city. | 2022-01-28 | 7.9 |
 | 04 | Episode 4 2022-01-28 | 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. | 2022-01-28 | 8.3 |
 | 05 | Episode 5 2022-01-28 | Martial law is imposed on the city. When Cheong-san is separated from the rest of the group, On-jo leads a mission to use a drone to locate him. | 2022-01-28 | 8.2 |
 | 06 | Episode 6 2022-01-28 | The group clears a path to Cheong-san using sound to draw away zombies, but a new type of threat surfaces. Nam So-ju breaks out of the quarantine camp. | 2022-01-28 | 8.2 |
 | 07 | Episode 7 2022-01-28 | 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. | 2022-01-28 | 8.3 |
 | 08 | Episode 8 2022-01-28 | Jae-ik and his crew run into a student from the school. Na-yeon works up the courage to face her peers. The group shares confessions around a fire. | 2022-01-28 | 8.5 |
 | 09 | Episode 9 2022-01-28 | A disturbance at the camp shifts the military's understanding of the virus. A thunderstorm provides cover as the group agrees to keep on moving. | 2022-01-28 | 8.3 |
 | 10 | Episode 10 2022-01-28 | The auditorium quickly becomes a trap for the two newly united teams of survivors. Byeong-chan's video logs reveal a drastic solution to the crisis. | 2022-01-28 | 8.0 |
 | 11 | Episode 11 2022-01-28 | Though a surprise protector provides the group safe passage to their next stop, Yoon Gwi-nam is not far behind. The military makes a grave decision. | 2022-01-28 | 8.4 |
 | 12 | Episode 12 2022-01-28 | The students make it to the quarantine camp, each of them weighed down by tragic loss. Months later, they hang on to hope for a survivor. | 2022-01-28 | 8.2 |
