When her husband's drug addiction destroys her perfect life, Jane (Maggie Siu) is forced to support herself and her young daughter, Ling, by taking a job as a security guard. One night Ling sees a soaking wet child doing homework at her desk. Eventually, Jane also felt that something weird was in the house; there was some strange noise all the time and seems like someone was peeping on her. Jane found out that the house was haunted--half a hear ago, a young woman named Yeung drowned her son Kenny and hanged herself to death in order to revenge on her husband Kam, who was having a mistress...