Episode Summary

The investigation focuses on quicklime as the fire's source and explores the complex relationships between Gao Yarui, Yu Fan, Jin Yan, Fang Ni, and Cheng Sisi. Evidence points to Jin Yan, who, motivated by revenge for past bullying and Yu Fan's inaction, manipulated Yu Fan and ultimately caused his death. The episode reveals a history of bullying, betrayal, and hidden motives among the group.

Spoiler Alert

The investigation into the fire incident intensifies as Shen Ye analyzes the testimonies of the four individuals involved. He believes Gao Yarui's account is the most credible, reasoning that people are most truthful when they are the ones being threatened. Shen Ye outlines two primary possibilities: either one person intended to kill Gao Yarui by switching out the prop water, a high-risk scenario, or three people conspired together to kill her. Xu Tongsheng adds that the victim, Yu Fan, should not be ruled out as a potential target.

It's suggested that Yu Fan, while carrying Gao Yarui's bag, might have switched the prop, and that someone else might have wanted to harm Yu Fan, thus leading everyone to the wrong room. Xu Tongsheng has Mao Mao re-examine the physical evidence at the point of ignition. They find a significant amount of quicklime mixed with magnesium powder. This mixture, when exposed to water, generates intense heat, easily igniting flammable materials. The large quantity of quicklime is identified as the likely source of the fire.

Back at the police station, Shen Ye continues to discuss who had the opportunity to place the quicklime. Shen Yi arrives to deliver food for Shen Ye, mentioning an upcoming two-day closed-door lecture. Li Dangui guides Shen Yi to the hall and informs Shen Ye. While Shen Ye is getting the food, Shen Yi inadvertently asks Xu Tongsheng about his hometown, prompting Shen Ye to scold Shen Yi for being too inquisitive.

During their meal, Shen Ye and Xu Tongsheng review the surveillance footage again, discovering that the ignition point was in a blind spot. They decide to re-interview the three individuals. When questioned, Fang Ni reveals that before Yu Fan met Gao Yarui, he was closest to Jin Yan. After Gao Yarui began bullying Yu Fan, Jin Yan would sometimes stand up for him. As for Cheng Sisi and Yu Fan, their relationship was very strained. Gao Yarui had instructed Yu Fan to record a conversation between Cheng Sisi and her advisor. Therefore, Yu Fan was the one who actually carried it out, while Gao Yarui was simply evil. Cheng Sisi would not stand it if even a cowardly person like Yu Fan could ride on her head.

Cheng Sisi, when asked about the relationship between Yu Fan and Fang Ni, states that Fang Ni also had issues with Yu Fan. Gao Yarui had initially promised Fang Ni regular financial support but later stopped paying. Fang Ni threatened to expose Gao Yarui's misdeeds to get the money. Because her mother was no longer selling pancakes outside the school, she wasn't worried about being threatened. However, Gao Yarui had Yu Fan present photos of Fang Ni's mother selling pancakes elsewhere. Cheng Sisi even believes Fang Ni could be the murderer, reasoning that if it weren't for Yu Fan, Fang Ni's pretense of being from a wealthy family wouldn't have been exposed, and she wouldn't have been threatened by Gao Yarui. Compared to Fang Ni, Cheng Sisi is more straightforward, speaking her mind directly.

When Jin Yan is questioned, she expresses deep sadness, claiming that she and Yu Fan were childhood friends. She says she had advised Yu Fan to leave Gao Yarui after witnessing the bullying, but Yu Fan wouldn't listen, having always been weak-willed. Their relationship gradually became distant, but there were no direct conflicts.

Gao Yarui also demands to accuse the other three. She claims that Fang Ni and Cheng Sisi are obvious suspects. As for Jin Yan and Yu Fan, Gao Yarui believes their relationship was fake, recalling an incident where she bullied Jin Yan, and Yu Fan stood by without intervening. Jin Chun makes a new discovery: Yu Fan seemed strangely unfazed and even laughed while burning. Previous interviews with classmates revealed that Yu Fan was mentally unstable for a long time before the incident.

Further review of the surveillance footage shows Yu Fan making a phone call before the incident, suggesting he was psychologically manipulated. Xu Tongsheng suspects the caller was Jin Yan. They re-examine the video of Gao Yarui bullying Jin Yan and launch another round of questioning, aiming to break through Jin Yan's defenses.

When it's mentioned that Yu Fan was present during the bullying incident, Jin Yan feigns surprise, but her reaction is seen as a giveaway. Yu Fan had originally planned to teach Gao Yarui a lesson through the role-playing game. After informing Jin Yan, Jin Yan, resenting Yu Fan for not standing up for her, plotted to kill Yu Fan. Jin Yan still denies it, but Shen Ye presents evidence of quicklime residue found on Jin Yan's clothes on the day of the incident.