When a localized science experiment goes horribly wrong at Hyosan High School, a mysterious virus begins to spread, turning students into flesh-eating zombies. With no outside help and limited resources, a group of trapped students must navigate the chaotic hallways, classrooms, and rooftops to survive the night. As the infection spreads rapidly throughout the city, the students are forced to confront their own fears, betrayals, and the harsh reality of their situation. Beyond the immediate threat of the undead, the series explores themes of social hierarchy, bullying, and the moral decay of society. As the military attempts to contain the outbreak, the survivors must decide who to trust and how far they are willing to go to stay alive. The story balances intense horror sequences with emotional character arcs, highlighting the resilience of youth in the face of an apocalyptic catastrophe.