Tonton Film Ulterior Motive (Bie you dong ji) (2015)

Originally living a happy and stable life, things have become clouded for rich heiress Ye Shuang (Qin Lan) after the unexpected disappearance of her husband Ling Feng (Archie Kao) and daughter. After consulting with her father Ye Cheng (Simon Yam), Shuang decides to call the police, where she re-encounters her ex-boyfriend, Yao Jie (Gordon Lam). During the investigation process, Jie finds this million-dollar ransom kidnapping case to be a misty mystery. Specializing in investigating by starting from minor details, he targets Cheng as a potential suspect. At this time, Cheng's activities has also become suspiciously strange. When the mystery seemed to have dispersed, Cheng dies from an accident. At this time, clues from a murder case that took place 20 years ago begins to surface. Behind the mysterious kidnappings lies the ulterior motive.