该片以大地震后荒废的首尔为背景，讲述聚集在此地唯一剩下的“皇宫公寓”里的生存者们的故事。
Five members of the mountain bike club, Sangaja. To ride a mountain bike, we head to Chiaksan Mountain, where Min-joon's Uncle villa is located. After arriving at Chiaksan Mountain and enjoying the ride, strange things began to happen to the party…. And something unidentified chasing them! A desperate survival game for Sangaja's party to survive on Chiaksan Mountain begins.
