After a close call with a deadly epidemic and an attempt on the emperor's life, the imperial court of Qudu is in turmoil. The emperor is determined to hold someone among the noble clans accountable, a desire Shen Zechuan and Xiao Chiye are prepared to use to their political advantage. The chaos gives them another opportunity as well--a chance to investigate the suspected mastermind behind the fall of Zhongbo five years ago.

Yet as they delve deeper into the past, new dangers emerge in the present. For every move they make, their unseen adversary seems always a step ahead, driving them into a trap from which there is no way out. As Shen Zechuan and Xiao Chiye's lives grow more and more entwined, both find they are increasingly reliant on each other. But when Xiao Chiye extends a hand in their most desperate hour, will Shen Zechuan take it?