Modern science student Chen Feng fails a job interview and unexpectedly time-travels into the body of a failed scholar during the Zhenguan era of the Great Tang, possessing a unique ability to travel back and forth between two worlds. Just as an imperial proclamation is posted high, with Empress Zhangsun severely ill and seeking a physician, he resolutely unvells the proclamation and saves the empress using modern medicine. Two-year-old Princess Jinyang in the palace is innocent and cute, deeply touching Chen Feng's heart. Flipping through history books, he is shocked to learn that the empress, Princess Jinyang, and Princess Changle are all doomed to die prematurely. To rewrite this destined tragedy, he frequently shuttles between modern times and the Great Tang—conditioning the empress's body and caring for the little princess on one side, while helping Li Shimin solve his dilemmas on the other, writing a unique legend of the Great Tang across ancient and modern times.