Police detective Huang Huo-tu, a Waisheng ren in Taiwan, has relegated himself to a mundane job as a Foreign Affairs Officer as self-punishment for blowing the whistle on corruption in the force, and his colleagues have turned their backs on him. His young daughter is left traumatized after being taken hostage in a gun battle, and his wife Ching-fang is filing for divorce. Huang is on the verge of a severe nervous breakdown. A series of bizarre deaths in Taipei baffle local investigators, including a Catholic priest of foreign nationality found disemboweled. The priest is involved in the Taiwan-US military trade, so FBI agent Kevin Richter is called in to help. Huang, who can speak English, is made his liaison. Kevin, the topmost serial killer expert in the field, was previously investigating a series of murders in US in which all victims appeared willing to die. The crime scenes imply the involvement of supernatural forces. In one case a businessman froze to death in his office in the middle of a heatwave; in another the mistress of a prominent official called the fire department and was later found burned to death - with no sign of a fire ever occurring in her apartment. Richter is skeptical but Huang, who is more receptive to supernatural possibilities, suggests they investigate a local cult. After consulting a scholar in Academia Sinica, Huang and Kevin find that the killings follow a Taoist belief that one must fulfill five forms of suffering required to become a Xian, an immortal being. According to legends, the one who can perform the five rituals is born with double pupils in one eye. They also find that all victims have done something against their conscience, and that a kind of fungus was used to induce hallucination, pleasure and guilt which made the victims kill themselves. An advanced technology was used to spread the fungus, and the Police trace this technology to two bosses of an electronics company in Hsinchu Science Park. The men has spent their fortune and technology to move a Taoist temple into their company, where many cult believers gather. The police enter the temple, but the cultists perform a ritualistic massacre, killing many officers and cultists alike. After the massacre Kevin and Huang find a seemingly innocent girl who survived, and the case is closed. The next day Huang finds Kevin dead, having pulled out his own tongue, which is the fifth suffering required. Huang finds that both he and Kevin were infected with the fungus by the girl. Huang begins to hallucinate, tormented by the guilt he feels for his wife and daughter, and returns to the temple to confront the girl survivor, who is revealed to be the cult's leader. The girl has the double double pupil in her eye and believes that by having Huang kill her, she can complete the fifth requirement and become immortal. Huang kills the girl and is nearly overwhelmed with hallucination and guilt, but in the end he is allowed to return to his wife and child. The film ends with a Buddhist Gatha, which in the late and DVD version is "因愛生憂,因愛生懼,若遠離愛者,無憂亦無懼。" but in earlier versions is "love is immortal"
The film is a Columbia Pictures production, and the director Chen Kuo-fu, at the time, was the head of Columbia Pictures' Asian branch. It is one of a series of attempts by Columbia Pictures to invest and produce Asian movies with its Asian branch. The film impressed Taiwanese directors with its "Hollywood way" of filmmaking. With this film the director Chen Kuo-fu accumulated his experience in international collaboration and went on to work in China. The film's assistant directorWei Te-sheng and producer Jimmy Huang said they were stimulated by the big-budget effects of the film, and determined to make a movie on big budget. They later collaborated in local hit Cape No. 7 and big budget epic Seediq Bale. The film's screenwriter Su Chao-Pin later directed Silk. Leon Dai, a supporting actor, later directed No PuedoVivir Sin Ti. They said that they were stimulated by this production.
