"Flowers and Crime" tells about women who are going to the abyss of crime in the new era. The tortuous process of the public security organs' difficult detection of cases is shown, alluding to the abnormal psychology of criminals today, and exploring the psychological transformation process of female criminals from normal people to criminals step by step. Ma Dong, the captain of the criminal police team, was in charge of a bizarre local death case, but as he gradually unearthed the truth of the incident, Ma Dong found that there was no real murderer. Everyone involved in this case is an invisible murderer.
Ma Dong was punished and transferred to Yuqing City to start working. On the first day, he met female police officer He Yuqing who was chasing the suspect. After receiving the call, Ma Dong went to the crime scene and found that the victim was Wang Xiaomeng, a student at the local university campus. During the investigation by Ma Dong and others, the person in charge of the students tried to evade responsibility. Ma Dong investigated the student's dormitory overnight and found that the relationship between the deceased and several of his roommates was ordinary. Later, they found the sex video of the deceased, and they began to realize that the incident was far from simple as they imagined.