Au Yeung Wai Yip is a private detective who has been focusing on missing persons and adultery investigations for many years. One day, he received a "special" commission: the owner of the travel agency had asked him to investigate his girlfriend, who happened to be Au Yeung Wai Yip’s wife.Being a private detective, he is used to looking for the truth with cold eyes for his clients, but he finds it difficult to face the truth about their own marriage. Unable to withstand his inner torment, Au Yeung Wai Yip gave up on another ongoing case - a client's search for his missing fiancée - and went to the hotel to catch the adulterer. Unfortunately, the marriage could not be saved in the end, and the client's fiancée was killed after he left. A seemingly ordinary affair turned into a murderous incident!