The Twelve Hours of Chang 'an was a novel set in the Tang Dynasty. The story mainly took place in Chang' an City in the late Tang Dynasty. In this context, the Tang Dynasty experienced a series of political, economic and cultural crises, but also ushered in a new political structure and era change. Through the adventures and struggles of the protagonists, the novel shows the profound influence of the social turmoil and political changes in the late Tang Dynasty, and also reflects the good and evil of human nature and the choice of morality.