Confession of Pain

Confession of Pain is a 2006 Hong Kong crime drama film directed by Andrew Lau and Alan Mak, starring Tony Leung, Takeshi Kaneshiro, Shu Qi and Xu Jinglei.

Three years later, Yau discovers that his girlfriend had actually cheated on him and she was waiting at a bar for her secret lover on the night she died. Her secret lover did not show up that night because he was involved in a car accident. Yau initially thought that he will be angry with his girlfriends lover, but he ends up taking care of the comatose man in the hospital. Yau gets over the unhappy incident and falls in love with Hung, a girl who sells beer in the same bar.Laus wife, Susan, is the daughter of the billionaire Chow Yuensing. One night, Lau and two accomplices break into his fatherinlaws residence, where they kill Chow and his butler, Uncle Man. Later, Lau lures his partnersincrime to a rundown house and murders them, after which he attempts to make the scene seem as though the two of them killed each other in a dispute over the loot. Susan is not convinced that only the two killers were involved, so she hires Yau to help her investigate further. She has also become paranoid after her fathers murder, so Lau has to discreetly give her pills to calm her down and put her to sleep. ........

Source: Wikipedia