Overview:YAU has fallen into the sea. CHAK-LAM finds the incident suspicious. YAN does not agree with him though, believing it is no more than an accident that she fell into the sea when they went boating. TUNG finds it unreasonable that YAU would go boating with YAN, when she already had an appointment with CHAK-LAM the same day. SANTOS visits TUNG at her agency. He tells her YAN knows quite a few people in the police force. With a view to speeding up her investigation, he will send an officer who has been trained in the Scotland Yard to help her. It is a real surprise that the officer is none other than SHU. SHU has taken some material to TUNG, including a notebook of CHAK-LAM’s late father. CHAK-LAM finds that one page is missing in the notebook. SHU figures out the content of the missing page with little effort. NGAU praises him. SHUI feels jealous. TUNG discovers that the accident took place after the date of the entry of the missing page……