Li Xifeng, who entered the palace seeking revenge for his father, was unexpectedly chosen to become a princess and sent to the Tujue to gather military intelligence. Li Xifeng initially intended to use the power of Khan Ji Lie to avenge his father, but he discovered that Ji Lie’s reason for seeking the marriage alliance was because his elder brother had become a hostage in the Tang Dynasty, and marrying her was just a means to manipulate the Emperor of Tang Dynasty. Behind Ji Lie’s attempts to please her, he also intended to exploit her princess status to gather information, but he found out that Li Xifeng was a fake princess. As the two individuals, harboring their respective grudges, went from concealing the truth to falling in love, they eventually found the happiness they desired.