Su Ci is assigned to investigate Xu Zhi’s murder case. She finds that a lot of traces in the crime scene seems to be similar to the serial murder. Later on, Su Ci and Pei Zhao finds trace that proves the murderer of Xu Zhi is not the same serial murderer they were investigating of. It seems someone does not want Xu Zhi to get married with Prince Qi. (Source: Viu)