Jian Haoche, the sports committee member of Class 4, Grade 7, is well versed in the history of the Qin Dynasty, but he bursts into tears whenever he mentions the death of Qin Shihuang and the demise of the Qin Dynasty. The same goes for Qin Mo, the history class representative. This attracted the attention of squad leader Yang Yuan, and his intuition told him that the two people were related. On his way home from school, Yang Yuan saw Jian Haoche and Qin Mo walking into Qin Mo's house together, so he followed them in. Unexpectedly, Yang Yuan traveled back to the Qin Dynasty and discovered that Qin Mo was Qin Shihuang and Jian Haoche was Li Si. The two men had already discovered the conspiracy of Hu Hai and Zhao Gao, but Qin Shihuang was already sick and unable to compete with them, so he passed away with regret. After his death, he was reincarnated as Qin Mo, the history class representative. By chance, Qin Mo discovered Jian Haoche's identity, and joined forces with him in an attempt to travel back to Qin and restore the rule of the Qin Dynasty. Yang Yuan then worked with the two to eradicate the rebels and restore the Qin Dynasty. He also married Haoyue, the adopted daughter of Qin Shihuang. But history repeats itself again, can they get over this hurdle?