On a rainy night, Wang Xingjun, an on-duty worker at a metal processing factory, received a package, but he didn't buy anything recently. There was a loud explosion, and the courier brother, who put down his things and left, lit a cigarette, and the fire was blazing in the duty room behind him.
Du Cheng took the police to the scene to investigate, and only found the remaining express boxes and some toy fragments at the scene. Du Cheng worked overtime until late at night to check the unsolved bombing cases in the past. Shen Yi, who was going to go home, decided to stay and accompany Du Cheng to look at the files. The two were busy all night, and finally when dawn broke, Shen Yi discovered that there were also toy fragments on the scene of an explosion.
The first explosion occurred in an apartment, and the victim, Zhao Jianyu, was seriously injured and is still in a coma in the hospital. According to the toy fragments left at the scene, Du Cheng determined that the two cases were committed by the same person, which is likely to be a serial bombing case. Director Zhang ordered Du Cheng to solve the case within a time limit.
Jiang Xue restored the bombs used in the two cases. She believes that in the first case when Zhao Jianyu was injured, the bomber had little experience in making bombs, and in the second case when Wang Xingjun was killed, the bomber had already made bombs. It has been improved, so the power is much greater than the first time. However, the bombs used in the two cases were homemade, and the raw materials were easily obtained, so it was not meaningful to pursue them further.
When discussing the case, Du Cheng believed that the two cases were targeted retaliation. Jiang Feng investigated that Zhao Jianyu and Wang Xingjun were working in the same metal processing factory, and they belonged to a subordinate relationship. During the visit, Shen Yi found the vouchers of Brother Peng Xiaoguan at both Zhao Jianyu and Wang Xingjun's homes. After investigation, it was found that Zhao Jianyu and Wang Xingjun had quarreled with the waiter in Brother Peng Xiaoguan not long ago. Has been fired by the restaurant manager Li Hui. Shen Yi suspected that the service bureau was a bomber, and Du Cheng hurriedly contacted an EOD expert and rushed to Li Hui's house.
EOD experts found only a clock in the courier at Li Hui's house, when a car on the bridge across the sea exploded. The victims of the third explosion were Zhang Weifeng and his girlfriend Gao Miao. Du Cheng rushed to the scene after receiving police information, and Shen Yi found pieces of toys again at the scene. At the same time, Jiang Feng also found the detained waiter in the detention center, so he determined that he had no time to commit the crime at all. The survivor of the first bombing, Zhao Jianyu, was already sober. Du Cheng and Shen Yi asked him to understand the situation, but Zhao Jianyu did not tell the truth.
Jiang Feng brought back news that Zhao Jianyu and Zhang Weifeng had attended the same summer camp when they were students, and they both dropped out of school after the summer camp and went abroad, and only returned to China recently. Li Han found out that Zhao Jianwei and Zhang Weifeng had an accident when a student fell off a cliff when they participated in the summer camp. Li Liankai, who fell to his death, was in a group with them. The summer camp was arranged in a group of four, and the other person was named Liu Xiaochen.
Li Liankai, whose parents were divorced, lived with his father, Li Weijun, who was a courier. Du Cheng came to Li Weijun's residence with a search warrant. Although Li Weijun was not caught, he found equipment for making explosives in the attic. Shen Yi found four weird portraits in the room. He wanted to go back to the bureau to study it carefully. Du Cheng asked him to hand over the unknown drugs found at Li Weijun's house to the forensic doctor He Rongyue.
He Rongyue analyzed that the unknown drug was used to cure mental illness, and Shen Yi learned that Li Weijun suffered from facial blindness. According to the painting characteristics of the four portraits, Shen Yi perfectly restored the portraits of Li Weijun's four targets, and told everyone that Wang Xingjun was not Li Weijun's target, but that Li Weijun misunderstood Wang Xingjun as Liu Xiaochen due to his face blindness. Jiang Feng felt that it was time to go to Liu Xiaochen's house for control. Shen Yi proposed to go to the fourth toy store run by Lin Zhijie in the portrait. Although he was not on the list of summer camps, he also had a record of going abroad, and Shen Yi firmly believed that he was blind. Li Weijun did not know that he had killed the wrong person.
Jiang Feng reported the situation to Du Cheng, when Shen Yi was in the toy store.