A scuba diving trip turns into a nightmare when psychiatrist Gao Jing (Angelica Lee) and her boyfriend Guo Dong (Guo Xiaodong) meet tragedy at sea. Suffering from memory loss after the incident, Gao Jing can't remember what exactly happened in the ocean that day, and all that is recovered of Guo Dong is a headless corpse. Upset that Gao Jing is going ahead with the funeral, Guo Dong's sister Xiao Kai (Isabella Leong) angrily sets out to find her brother's head. Gao Jing looks for closure through therapy but only ends up with more questions and heartache. When her patient Simon (Chang Chen) claims that he can see Guo Dong's ghost, Gao Jing seeks his guidance to open her eyes and mind to the other side. Soon she's seeing visitors of all sorts, but no Guo Dong. At this time, a strangely eerie Xiao Kai suddenly returns to Hong Kong with her brother's head. But is it really Guo Dong's head that Xiao Kai has brought back?