Episode 18 recap: Fox Ridge Town sees another locked-room murder.

Zhao Xiao Liu believes that the most suspicious person now is Lang Zhengcai. Zhao Xiao Liu even entrusted his personal jade pendant to Lang Zhengcai and asked him to seek help from the county magistrate. Yin Qiao was still paying respects to her father and third uncle in the ancestral hall when suddenly she heard her second uncle scream. Concerned that the culprit might target their family again, she followed the person who screamed outside. Fortunately, her second uncle was unharmed, but Yin Qiao left first.

Li Zi Fang, seeing this, became very worried about Yin Qiao and hurriedly followed her. However, they were stopped by Song Ci, as neither of them knew martial arts. It was best to wait for others to come and support them. Shen Xi Yue, upon seeing this, threw her sword to Yin Qiao, but the black-clothed person managed to escape. Bai Xue Yan quickly went to check on her second uncle's condition, luckily finding him unharmed.

After entering, Song Ci noticed that the black-clothed person had torn open her second uncle's clothes, indicating they wanted to examine the scars on his body rather than take his life. This suggests that the person is familiar with the entire estate's layout. Initially, Bai Xue Yan suspected Yin Xin, considering she hadn't appeared since the death of the Yin clan's master. However, Shen Xi Yue directly refuted this and stated that Yin Xin's martial arts were comparable to her own, indicating that she wasn't the culprit.

At that moment, Chen Yi arrived and claimed to have gone to make medicine for her second uncle. Chen Yi believed that if she had been present, she could have apprehended the assailant. Yin Qiao mentioned that she planned to meet Lang Zhengcai the next day, which worried Chen Yi. Song Ci proposed going with Chen Yi to retrieve the medicine she had prepared, leaving Chen Yi stunned.

Currently, many speculations are still circulating, and the exact details of what happened that year can only be obtained by questioning Lang Zhengcai. Bai Xue Yan had been waiting for Song Ci to return, wanting to know her condition. Song Ci stated that she hadn't felt anything particularly unusual lately. After Bai Xue Yan took her pulse, she discovered that Song Ci's body, which had been weak in the morning, now seemed normal, which was quite strange.

The next morning, as everyone prepared to leave, Yin Qiao pulled Li Zi Fang aside. Li Zi Fang confessed that he liked Yin Qiao, and Yin Qiao also had a favorable impression of Li Zi Fang. However, because Li Zi Fang needed to continue investigating his father's matter, they had to leave the Yin family estate for now.

Now, Song Ci and the group are heading to find Lang Zhengcai. Only by uncovering the truth behind everything can they find a resolution.

Perhaps the next target of the killer is Lang Zhengcai. Instead of waiting for the killer to show up, they decided to take the initiative. Song Ci and the group first arrived at the inn where Lang Zhengcai was staying and kept watch nearby.

Bai Xue Yan also told Song Ci that the reason he fainted was because he accidentally misplaced a certain medicinal herb. It seemed that Yin Chao had been in a coma due to the same medication, and the killer had precise knowledge of drugs. They made Yin Chao unconscious without causing death. Yin Qiao was very worried about them and followed along. Instead of joining Song Ci and the others, Yin Qiao went directly to find Lang Zhengcai. The soldiers knocked on the door, but there was no response from Lang Zhengcai's room. When they broke down the door, they found Lang Zhengcai and his wife lying in a pool of blood.

Now, it was another locked-room murder. Lang Zhengcai's deputy, Jia Gang, was extremely agitated. Recently, Lang Zhengcai's wife had also claimed to feel possessed by a ghost. Two hours ago, a Taoist priest had visited, claiming to be able to treat Lang Zhengcai's wife. Jia Gang let the Taoist priest inside, and later, the priest accurately diagnosed her illness and performed an exorcism. The wife closed the door, and Yin Qiao and Jia Gang rushed in, only to find the wife and Lang Zhengcai dead.

Song Ci quickly examined the scene. It was a perfect locked room, and they needed to figure out how the killer had accomplished it. Jia Gang also found it very strange because his wife never locked the door. Why would she lock it here? Soon, guards found the discarded Taoist robe not far away, indicating that the so-called Taoist priest was also fake.

Meanwhile, Li Zi Fang and his group were investigating on the street when Li Zi Fang noticed Yin Xin being chased by several people. Shen Xi Yue quickly went to help and drove the attackers away. Song Ci also examined Lang Zhengcai's body and the mortician confirmed that his wounds were deliberately inflicted on a major artery, causing him to bleed to death.

Song Ci continued to analyze the locked room, while Zhao Xiao Liu suspected Lang Zhengcai's wife, Yin Lan, as the killer. Song Ci had a sudden realization and quickly went to examine the body. Afterwards, she had someone bring the key to the room, and Li Zi Fang compared it to the lock that Chen Yi had cut when Lai Fu was killed.