The protagonist, Park Jisoo, is a high school student who finds herself stranded inside the school along with her classmates, including her crush, Lee Hye-young, and her best friend, Nam Yeo-kyung. As they try to figure out what is happening and how to escape, they are forced to confront their fears and work together to survive.
The show blends humor with horror as the students navigate the zombie apocalypse, facing off against their former classmates who are now undead and hungry for human flesh. It also touches on themes such as friendship, romance, and the pressures of high school life.
As the story unfolds, the characters must make difficult choices and come to terms with their own mortality. Despite the dire situation they find themselves in, they also find moments of hope and resilience in the face of overwhelming odds.