Researcher Bo Dai, along with a team of precision instruments and the Serious Crime Unit, investigated the appearance of a ghost at the scene of the incident. Li and Bo Dai conducted a check with Wen, discovering that he could see light invisible to ordinary people. To verify whether Wen had the "third eye," Li and Wen went deep into the mountains of Lantau Island to find a Taoist priest. When they left, they got lost and encountered a heavy rainstorm. Li fell and was injured; due to poor mobile phone reception in their location, Bo had no choice but to help Li take shelter in a small pavilion; the next day, Bo found that Li had fallen into a coma due to an inflamed hand injury... Heng invited Chen Gui to the police station for questioning again, and Chen Gui finally admitted his guilt; Bo suggested letting Wen return to the unit for an experiment, eventually uncovering the mystery of why Wen saw ghosts... Li received a call from Liang, saying that he and An had been in a traffic accident; Liang insisted on his innocence and thus requested Li to ask Bo to be his expert witness...