Episode Summary
Xu Tongsheng's experiments prove the initial fire cause theory wrong, exonerating Chen Xue. A new suspect, mechanic Wang Xi, emerges with a revenge motive against Han Pei. Wang Xi confesses, seemingly closing the case. However, Xu Tongsheng's suspicions persist, and clues about Han Jun's unusual return route and perfect memory suggest a deeper mystery remains, despite the official closure and the formation of a new fire investigation unit.
Spoiler Alert
The episode throws a major curveball in the investigation of Han Pei's apparent death in a car fire. Xu Tongsheng conducts experiments at the fire station, proving that a lighter couldn't have ignited the fire-resistant floor mats in the car, even with a Bunsen burner. Only a high-pressure torch could achieve that. He rushes to Jin Chun's office, excited because Chen Xue confessed, but Xu Tongsheng's findings immediately debunk her confession, establishing she's not the culprit.
Xu Tongsheng remembers some red dots at the neck of the corpse. He inquires whether the cause of death can be traced. Jin Chun says the red dots existed before the victim's accident. As for the time, it can not be deduced. Xu Tongsheng goes back to the fire station for more experiments.
Shen Ye, crestfallen, reports how Xu Tongsheng overturned the evidence. Wu Yong suggests Shen Ye needs to be more assertive in his casework and not blindly follow others' opinions. After Shen Ye leaves, Wu Yong receives a phone call, promising to push Shen Ye to close the case quickly.
Xu Tongsheng shifts his focus to the fire's origin. He finds burnt rubber fragments at the scene, theorizing that friction between the tire and the road caused the fire, with the fragments landing on the victim's neck, causing the red dots. Shen Ye concludes that someone else was at the scene. If the other person intended to kill Han Pei, they would have gone to the hospital to confirm the victim's identity. Even if it was Han Jun who survived, he would be in danger.
Xu Tongsheng goes to the 4S shop (auto dealership) to check Han Pei's car maintenance records, only to find Shen Ye already there. The owner says Wang Xi, the mechanic, serviced Han Pei's car that day. Shen Ye requests the records, and Li Dangui goes with Wang Xi to get the ledger. Suddenly, Wang Xi flees through the back door. Shen Ye has Li Dangui and Mao Mao stay put, while he and Xu Tongsheng chase after Wang Xi. Familiar with the area, they quickly apprehend him.
Brought to the Bixi Sub-bureau, Wang Xi initially claims he just performed routine maintenance. Shen Ye presents the 4S shop owner's statement, forcing Wang Xi to confess. He reveals that he specifically serviced Han Pei's car. A year ago, his mother was rushed to the hospital, but Han Pei demanded Wang Xi return to the 4S shop for a minor issue. After meeting with Han Pei, Wang Xi mentioned his mother's hospitalization, but Han Pei snatched and smashed his phone, preventing Wang Xi from seeing his mother one last time. Driven by revenge, he experimented with causing fires through tire and wheel hub friction. After the car fire, he went to the hospital to confirm the victim's identity, where Shen Ye spotted him.
At the closing press conference, Gu Nuo, the deputy captain of the Beixun City Criminal Investigation Detachment, expresses satisfaction with the investigation. Xu Tongsheng proposes establishing a special task force in Beixun City to investigate fire-related cases, consisting of himself, Shen Ye, and Jin Chun. The Criminal Investigation Detachment fully supports this, and Gu Nuo agrees.
A few days later, Gu Nuo informs Shen Ye that the application for the joint investigation team has been approved. Gu Nuo summons Shen Ye and Xu Tongsheng to his office, urging them to collaborate closely.
To celebrate the team's formation, Xu Tongsheng treats everyone to dinner. He subtly probes Huang Qi about Han Pei's background. Shen Ye insists the case is closed and discourages creating unnecessary tension. Xu Tongsheng believes both Chen Xue and Wang Xi might be lying. Li Dangui suddenly receives a text from the immigration bureau, revealing that Han Jun took a very obscure route when returning to the country. Shen Ye realizes there's more to the case. Just then, the hospital notifies them that Han Jun has regained consciousness, and the trio rushes to the hospital.
Han Jun shows little concern about Han Pei's fate, explaining that he left home at eighteen to live abroad, resulting in a distant relationship with his brother. Shen Ye asks why he didn't take the land route home, and Han Jun says his itinerary was arranged by Han Pei. Jin Chun, a former classmate of Han Jun, deliberately guides him to recall university memories. Surprisingly, Han Jun remembers things even more clearly than Jin Chun, confirming that the survivor is indeed Han Jun.
Back at the fire investigation office, Sun Ling calls Xu Tongsheng, informing him of her decision to leave Beixun. Regardless of what happened to her husband, Han Pei's death brings closure. Zhao Zhiyuan grants Xu Tongsheng access to the archives, hoping he can finally put the matter to rest.
