In the late autumn of 644 A.D. (the eighteenth year of Zhenguan), the 12-year-old Princess Li Mingda of Jinyang was seriously ill. The imperial physicians in the Imperial Medical Office were helpless, so they suggested that the Minister Li Chunfeng find a weak crown that matches Li Mingda's birth date. In the first year, a man was recruited as a son-in-law to celebrate the joy. In order to save his beloved daughter's life, Emperor Taizong Li Shimin had to try. Therefore, the imperial list of Li Shimin's son-in-law was posted on the gates of palaces and workshops in Chang'an City, and the poor scholars who lived in Pingkangfang all the year round Chen Hao uncovered the imperial list. On the night of their marriage, Chen Hao, a modern man who traveled through time, learned that Princess Jinyang was unconscious and dying. It turned out that Li Shimin recruited him as his son-in-law just to celebrate Princess Jinyang!