Modern project manager Chen Yuan accidentally traveled through the prosperous Tang Dynasty and was forced to form a crime-solving triangle with Pei Zhen, an upright military general, and Su Yuehua, the daughter of a Hu merchant from the Western Regions. When the blood oath between the prince and An Lushan appeared, they were involved in a conspiracy to overthrow the dynasty. The cold chalcedony awakens, the power of the ancient gods reappears in the world, and mortal bodies are forced to embark on the battlefield between gods and demons. In the flames of war in Tongguan, can they fight their way out of the gap between the world and the gods and defend the last backbone of the Tang Dynasty?
