A modern warehouse unexpectedly connects to a war-torn world a thousand years in the past. Jiang Wanqing, struggling to keep her business afloat, encounters General Huo Yanchuan, who is trapped in a desperate situation, through a mysterious iron door. Food, medicine, steel, tools, and other modern supplies continuously pour into the ancient world, quietly changing a situation that once seemed hopeless. From a supply trade spanning a thousand years to standing shoulder to shoulder defending a city and fighting their way through bloodshed, as modern supplies disrupt an ancient world in turmoil, the fates of these two people become irrevocably intertwined.