In her past life during the doomsday, Jiang Ning was betrayed by her boyfriend Yang Weicong and junior schoolmate Su Mengyao, and is reborn three days before the natural disaster descends. She awakens spatial abilities, frantically hoards supplies and builds a safe house, unites her childhood friend Zhang Chao and others, and gets to know the mysterious and powerful retired special forces soldier Huo Yishen. Several people join forces to guard the eighteenth floor. Facing Su Mengyao's delusional fantasies, as well as the greedy looting of Yang Weicong and her neighbors, Jiang Ning resolves crises with wisdom and force, exposes their evil deeds, and finally gains a firm foothold on the eighteenth floor, opening a strong path of doomsday survival.