All of Us Are Dead EP 4 [ENG SUB]

Cheong-san's mother arrives at the school, only to be quickly surrounded and killed by zombies, among them a zombie Gyeong-su. Police interrogate Byeong-chan, who confesses to creating the virus (named the "Jonas Virus") in an attempt to empower Jin-su against his bullies. However, it did not go as planned; Jin-su turned into a zombie and bit his mother, causing her to turn too. Byeong-chan says that he has since tried to find a cure, to no success. A horde of zombies suddenly swarm the police station. Byeong-chan is bitten and tells police detective Song Jae-ik that the cure to the virus is on his laptop in the school's science lab. He sacrifices himself into the horde, allowing Jae-ik and rookie police officer Jeon Ho-chul to escape. Meanwhile, Su-hyeok and Cheong-san retrieve a phone from the staff room. They are separated by zombies; Su-hyeok returns to the broadcast room, while Cheong-san is forced to flee with the phone. Cheong-san momentarily hides in the principal's office and witnesses Gwi-nam killing the principal. He flees again with Gwi-nam in pursuit. So-ju, a surviving crewmate, and the government officials board a rescue helicopter and are successfully evacuated.