There was an armed robbery at Jiufu Jewelry. Jiang Xue, a ballistics expert, discovered after investigating the scene that the gun used by the robbers in this robbery came from the same gun as the robbery in Fu 'an seven years ago. After the robbery progressed, Zhang Bureau asked everyone to carry a gun, even the painter had to carry a gun. Shen Yi couldn't shoot, and Du Cheng was a little worried, so he took Shen Yi to practice first and taught him how to use guns.

Du Cheng is checking the surveillance and looking for the whereabouts of the gangsters. I didn't expect He Rongyue to make new discoveries at this time. He Hong reported to the police station that her husband Mu Wei was missing and provided some information about related items. He Rongyue found Mu Wei's blood, just like the blood left at the jewelry scene. With any new discovery, Du Cheng immediately took people to Eric's home to search, but he didn't expect to find some new clues.

Li Han found that Mu Wei bought a plane ticket to Nanjing as Li Zhiqiang. Du Cheng learned that Mu Wei had bought a ticket and immediately went to the station to look for clues, but he didn't know where the person holding this ID card went. When Shen Yi was sent back to the police station by Du Cheng, she accidentally met a woman wearing sunglasses. She couldn't find a blue car. She remembered the secret of wallpaper in Muwei's computer and understood that Muwei was color blind.