Su Chang'an transmigrates into the body of a foolish young man in an ancient mountain village. His family is left with nothing: his closest relatives have fled with all their money, leaving behind a mountain of debt. Looking at his eldest sister, whose engagement has been broken off, his timid younger sister, and his mischievous younger brother, he activates a knowledge database spanning ancient and modern times. He turns foul-smelling mountain leaves into miraculous tofu and mosquito-repelling wild herbs into incense coils that earn a fortune every day. He only intended to scrape together enough to support his family, but unexpectedly, his eldest sister becomes a renowned chef and his younger sister a master embroiderer. Years later, the Great Yu Dynasty is prosperous and militarily powerful. A historian writes in his biography: 'This gentleman never once entered the imperial court in his lifetime. Yet his plows, seeds, tools, and methods have brought lasting peace and prosperity to generations.' He is truly the 'Prime Minister of the Mountains.'