A modern history graduate student transmigrates into the body of Yang Zhao, the eldest legitimate son of Yang Guang. At just sixteen, he takes control of the empire's destiny, carrying high-yielding seeds like potatoes and corn. He turns the tide and saves the Sui from crisis through four strategies: stabilizing grain supplies with seeds, controlling profits through salt reforms, strengthening the army with firearms, and opening up the seas with warships. Doted on by Yang Guang and Empress Xiao, he lays out his grand strategy from the start and wins their full support. He marries Changsun Wugou to win over the common people, helps Changsun Wuji rise to power, appoints Qin Qiong and Luo Shixin as his fierce vanguard generals, and entrusts Fang Xuanling and Du Ruhui with strategy. United in purpose, sovereign and subjects set out to conquer the world.
The aristocratic clans of Guanlong, Shandong, and Jiangnan harbor treacherous schemes, repeatedly poisoning supplies, intercepting grain, and colluding with the enemy. The Li clan hides its ruthless ambition behind a façade of benevolence, conspires with the aristocratic families, and flees to the Americas after its defeat, hoping to survive there. Yang Zhao first conquers Goguryeo and establishes his might, then puts down the anti-Sui rebels to eliminate internal threats, before wiping out the centuries-old aristocratic clans once and for all. He commissions colossal ocean-going ships, seizes vast amounts of gold and silver from the Japanese islands, conquers Tianzhu and claims a thousand li of fertile land for high-yield crops, then sweeps across the Western Regions, the South Seas, and the northern tribes, expanding the empire's borders by thousands of li.
Leading an army equipped with firearms across the five continents, he ultimately marches on the Americas for a final showdown with the Li clan. Qin Qiong beheads their generals, Luo Shixin captures their enemies, and Yuchi Gong joins forces with the black-and-white sisters to subdue Li Shimin, wiping out every villain. Yang Zhao introduces equal-field land reforms and overhauls the civil service examinations, breaking the aristocrats' monopoly on power. Chinese civilization spreads across the globe, and Yang Zhao, as the Dragon Lord of the Great Sui, forges an empire on which the sun never sets, ushering in an unprecedented golden age.
