The story is overlapped with two periods of time – the generation of 19-year-old boy and girl, Gyoo Bin and Shia and the generation of Joo Hyuk and Min Ji 10 years later. Gyoo Bin witnessed that his friend Min Wook is suddenly changed into a zombie and attacked Hyun Chul to death at school cafeteria. And when Min Wook tried to attack Gyoo Bin, a brave and bold Shia, who was strong enough to win the first prize in fighting competition, appeared and knocked down Min Wook. The peaceful lunch time is suddenly changed into a chaos. However, the real problem is that certain ages of students change into zombies to attack innocent people nationwide. Adults simply determine this event as the side effect of ‘Cotanol’, a stimulant, happening among only teenagers, so they all lock down teenagers in their school. However, instead of protecting or curing them, they plan to send children to army to protect adults. Gyoo Bin and Hyun Chul accidentally noticed their intention, so they planned to escape from the school with Se Chang. At the same time, other children also decided not to be oppressed their freedom anymore, and not to just wait for adults to prepare solutions. Therefore, they all cooperated together and crossed the gate with wires. Adults became super-contagious people to make other people zombies after being changed into zombies with unknown strokes. The ruined city is now full of living dead and debris of buildings. However, there still are survivors. Will they survive in this world filled with zombies?