One day before the end of the world arrives, two sisters face a choice, choosing the old house or the mysterious jade pendant. In her past life, Song Wan coveted the demolition compensation and chose the old house, while Song Yu, who was forced to choose the jade pendant, awakened space, bound an upgrade system, and relied on hard work to upgrade the 1-cubic-meter space into thousands of cubic meters, living a prosperous life in the apocalypse. Reliving this day, Song Wan snatches the jade pendant first and hoards supplies crazily, little knowing that the jade pendant only has one cubic meter of ordinary storage, and the one who bound the upgrade system is still Song Yu. Song Yu chooses the old house, cares for her parents attentively, relies on the system to transform the house into a safe fortress, and also helps surrounding neighbors get through hard times together.