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

A group of bullies led by Son Myung-hwan from Hyosan High School attack fellow student Lee Jin-su. Jin-su falls off the rooftop and is hospitalized. His father, Lee Byeong-chan, a science teacher from Hyosan High, realizes Jin-su has developed zombie-like behavior. Some time later in Hyosan High, one of the bullies, Kim Hyeon-ju, is bitten by an infected hamster in the science lab. Byeong-chan sees this and locks Hyeon-ju inside the lab, but she escapes the next day and collapses in English teacher Ms. Park's class in a zombie-like state. Hyeon-ju is taken to the school clinic, where she suddenly bites the school's nurse. An ambulance takes Hyeon-ju to the hospital. The nurse transforms into a zombie and attacks several students, who all get infected and start an outbreak inside the school. Students and childhood friends Nam On-Jo and Lee Cheong-San are in the cafeteria where more infected students make their way inside and panic breaks out.