The story follows Lin Xuan, a top-tier full-stack engineer who graduated from a prestigious 985 university. After being replaced by AI, he travels back in time to the Tang Dynasty and becomes the live-in son-in-law of the Zhao family in Qinghe County. Their tofu workshop is on the verge of bankruptcy, his fiery-tempered wife, Zhao Ling'er, constantly gives him a hard time, and the wealthy local tycoon Qian Wanguan secretly covets what the family has and relentlessly pressures them. Trapped in the lowest social position of ancient society with the soul of a modern man, will Lin Xuan resign himself to his fate, or use a thousand years of future knowledge to fight his way to success? As the attention of an imperial censor and an imperial merchant turns toward the little county of Qinghe, a storm of dignity, business, and romance quietly begins to brew. Meanwhile, a door that could take him back to the modern world is slowly opening through the choices he makes without even realizing it.