In the years since 1999, Hongzhou City, which had always been peaceful and tranquil, has seen a number of rapes and murders against young women. The victims' skin has been cut into strange blood daisy shapes by the murderers. The task of solving this shocking serial murder case is handed over to the police Liu Yibo and his partner He Chen. This battle of wits and courage to chase the murderer has lasted for 19 years...