Lin Min, who studied with Xu Yiduo together with Shen Yi, came to Xu Yiduo's home. She looked at the paintings in the studio and suggested holding an art exhibition. Shen Yi felt that there was no point in doing so.Lin Min noticed a painting created by Shen Yi, and this painting had been burned by Shen Yi seven years ago. This shows that this painting was copied by Xu Yiduo.Lin Min then advised Shen Yi to draw a real one instead, otherwise he would be cast aside if he copied the meaning of other people's paintings.After hearing this, Shen Yi didn't comment and hurriedly left with the painting.

When Ducheng visited the gallery, he discovered many paintings by Shen Yi. However, these paintings had been burned by Shen Yi seven years ago. The gallery owner identified the person selling the paintings from the photos as Xu Yiduo.Li Han found a video about Xu Yiduo's son, Xu Siwen, from Xu Yiduo's mobile phone. In the video, Xu Siwen asked Xu Yiduo to help him raise a huge sum of money.Ducheng suspected that Xu Yiduo was selling fake paintings of Shen Yi's works just to help Xu Siwen raise money.

Xu Siwen returned to Beijiang, and Shen Yi handed him all Xu Yido's paintings.Xu Siwen decided to sell all the paintings, and Shen Yi wanted him to keep some paintings as souvenirs. However, Xu Siwen believed that Xu Yiduo, who loved painting very much, did not like him at all, so he lived abroad all his adult life.Shen Yi asked Xu Siwen if he had received any remittances from Xu Yiduo, and Xu Siwen said that he had never received any money from Xu Yiduo.

In the interrogation room, Du Cheng told Xu Siwen that Xu Yiduo committed suicide after remitting money to him. Xu Siwen took out all the bank cards in his name and let Du Cheng check them at will.Du Cheng asked Xu Siwen to repeat what he said in the video. Xu Siwen bluntly said that he had very little contact with Xu Yiduo and his wife.

After watching the video carefully, Shen Yi found that the person in the video was not Xu Siwen. Du Cheng expressed doubts. Shen Yi explained that although the two were very similar, he could tell the difference between them through micro-expressions that could not be disguised.By analyzing the light in the video, Shen Yi discovered that the video was synthesized by AI face-changing technology.

Shen Yi sat in front of Xu Siwen. Xu Siwen wanted to watch the video. Shen Yi told Xu Siwen that Xu Yiduo cared about him very much, but did not dare to contact him for fear of disturbing his life, so he was deceived.Xu Siwen lowered his head to hide the tears that came from his eyes.

Through case correlation, Du Cheng discovered that fraud cases similar to this case had occurred many times, and Director Zhang ordered the case to be solved as soon as possible.As an information security company, Tongcheng is developing AI face-changing technology. The person in charge of technology in Tongcheng said that to complete AI face-changing, it is not only necessary to have a large number of photos of the people in the video, but also to record the same video in advance as a master before the face-changing.Li Han found all the fraud videos. Shen Yi drew portraits of the characters in the originals of the videos through careful observation and careful comparison. Du Cheng used the portraits to visit the victims' surrounding contacts, and finally found Zhang Xiaoxue, a housekeeping staff member.After Du Cheng and Jiang Feng went to the housekeeping company to investigate, they found that the victims of several fraud cases were Zhang Xiaoxue's service recipients, and Zhang Xiaoxue was then taken to the police station.

During the interrogation, Zhang Xiaoxue's performance was a little nervous but very calm, and there was no information about AI face-changing in Zhang Xiaoxue's computer, so the case was at a deadlock.Li Han suggested looking for clues from the social networking sites that Xu Siwen often used. After screening, Li Han found four IP addresses that frequently checked Xu Siwen's social accounts, and these four addresses pointed to Zhang Xiaoxue's address.

Zhang Xiaoxue was questioned again, and Shen Yi recalled the traces of male life he found in Zhang Xiaoxue's home. Zhang Xiaoxue explained that she had lived with her ex-boyfriend Hu Zhifeng, and the two had just broken up.Shen Yi asked about Hu Zhifeng's situation. Zhang Xiaoxue said that Hu Zhifeng was a computer salesman and often traveled on business.Li Han found out the location of Hu Zhifeng, and Shen Yi learned from Du Cheng that the sentencing of fraudsters was not severe.When he was about to take action, Du Cheng discovered that Shen Yi was missing. At this time, Shen Yi knocked on Hu Zhifeng's door with a painting.