Under the strong insistence of Chen Shaofeng, who was in charge of the command, the Haizhou City 810 case task force absorbed an administrator of the police station's archives room. This police officer named Xiao Yang was not worldly-wise, but gradually occupied the dominant position of the arrest team with his wisdom and calmness, and also attracted the admiration of the policewoman Fang Zhu. However, Xiao Yang was not a person who was good at understanding the world and was only immersed in his own world, so most of the time he was a narcissist and a psychopath in Fang Zhu's eyes. Another weapon hidden by Chen Shaofeng was the undercover police officer Chen Zhen, who was a sharp knife ready to stab the criminal's heart at any time. With the cooperation of him and Xiao Yang, the police frequently made gains and the suspects were arrested one after another. Chen Zhen, who was used to being cold, fell in love with Fang Zhu, who helped him when she saw injustice, in an unexpected encounter. This kind and brave girl deeply attracted him, but he could never approach her in her true face. As the case progresses, this group of smart, courageous and passionate people get along and adapt to each other over time, and slowly untie the knots in their hearts.