Due to government shuffle during the reign of Wu Zetian, the ambitious Di Renjie was relegated to a remote town in the east. Di showed extraordinary talent in case-solving, but as he probed further, more and more secrets were revealed. He embarked on a nationwide journey and solved many mysterious cases. In the end, he returned to Chang'an and reunited with his father. Together, they tackled a crisis that threatened peace and order.

Zhou Yiwei, Wang Likun, Zhong Chuxi, Ling Zi, Ta Ji, You Yongzhi, Zhang Jiayi, Zhang Ruoyun, Jerry Lee, Li Naiwen, Zhang Xilin, Liu Duanduan, Yin Xiaotian, Kaavie Wong, Yang Haoyu, Clara Lee, He Zhonghua, Yang Minna, Chen Duling, Yu Kailei