Zheng Shaopeng, a high school student, dozed off during a history lesson. When he awoke, he discovered that he had changed into the impoverished scholar Yang Lin and had traveled to the Danzhu Dynasty in the history textbook. Initially, Yang Lin struggled to adjust to life in the past, but when he applied contemporary ideas to create a few modest innovations, he won the villagers' affection and eventually discovered a feeling of identity of his own.

Yang Lin lived through a time of both internal and exterior unrest, experiencing battles and seeing the agony of the populace. By relying on his knowledge and abilities to acquire access to the court, he eventually oversaw the Danzhu Dynasty's efforts to combat internal corruption and repel formidable adversaries.

(Source: bilibili)