Black Holidays.

Detective novelist Ng Hong and his fiancée Leung Huen were invited by their friend Lam Chung to his New Territories mansion for vacation. Chung was dissatisfied with his mother for his arranged marriage, so he went home and divorced his wife. However when Chung's mother opened his room's door, Chung immediately ran away, jumped off the cliff and committed suicide. Hong felt suspicious, and began his secret investigation...