Modern woman Zhang Jin travels through the early Tang Dynasty and has a deep love with Li Yuanji, her childhood sweetheart. Unwilling to be broken up by her arranged marriage, she tried to reverse history and help Li Yuanji avoid the fate of the Xuanwu Gate Incident. However, the fight for the throne was cruel and ruthless, and she failed to save her lover after all. In the end, she used her life as a bargaining chip to beg Li Shimin to let go of the youngest son of the two princes, leaving endless regrets.
