"All Of Us Are Dead"|Season 1|Episode 2

On-jo and Cheong-san flee the cafeteria and take refuge in class 2-5 with their surviving classmates, including class president Choi Nam-ra, former delinquent Lee Su-hyeok, Cheong-san's best friend Han Gyeong-su, On-Jo's best friend Yoon I-sak, the entitled and arrogant Lee Na-yeon, Oh Jun-yeong, Kim Ji-min, Seo Hyo-ryung, Yang Dae-su, Jang Woo-jin, and Kim Min-ji. Not long after, an infected teacher makes his way into the classroom and suddenly transforms into a zombie and bites Min-ji, prompting the other students to flee and fight their way into another classroom. I-sak, however, becomes infected along the way and is thrown out the window, to On-jo's despair. When zombies try to break in, the students use a fire hose to climb down to the broadcasting room because Ms. Park is there. Meanwhile, Yoon Gwi-nam, a bully and Myung-hwan's henchman, hides in the cafeteria's kitchen with two students and a lunch lady. The school's archery team - including Woo-jin's sister Jang Ha-ri and her co-athlete Jung Min-jae - arrive and notice the situation at school. Senior students Yoo Jun-seong and Park Mi-jin are trapped in a restroom with infected student Lee Ha-lim, but are saved by Ha-ri and Min-jae. At the hospital, Hyeon-ju infects several other people, which leads to the virus gradually spreading throughout Hyosan.