Jae-yoon, a late military enlistee, and his girlfriend, Young-joo, break up over the phone over growing misunderstandings. But a zombie outbreak rocks the world. A national emergency is declared, a plane crashes in the city center, and Jae-yoon and his unit get trapped on top of a Seoul skyscraper. Young-joo risks the zombie-filled streets to find him. Can their love survive the apocalypse?
Jae-yoon and his direct junior, In-ho, head down to Eden Hotel, right below their air defense unit, for an errand. Upon arrival, they find a plane crashing into the heart of Seoul, and the hotel turned into a bloody chaos. Meanwhile, Young-joo and Jin-wook also confront zombies and team up with Tae-shik, who happens to be passing by. Together, they begin their fight for survival.