A sex-crimes specialist from New York travels to the Philippines to help his friend, a Manila homicide detective, solve a series of murders.
Adam Rourke [Robert Winston], a wise-cracking sex-crime specialist from New York, who talks to himself and carries an old, life-size dummy named Harvey in his suitcase, is called to Manila by old friend and chief inspector of homicide, Captain Miguel Ramos [Vic Diaz]. Girls have been turning up dead, found hanging upside down from trees with their wrists cut and their bodies drained of blood. The only lead is that the latest victim (Maria Cortez) was working at the Barrio Club. Adam suggests that a good way to approach the investigation would be for him to go undercover, posing as an American writer. Miguel agrees, but only on the condition that he and Adam have no contact with each other while Adam is undercover. Miguel's London-educated sister Sylvia [Katherine Henryk], however, takes an instant dislike to Adam's cavalier attitude, particularly his pooh-poohing the "unsophisticated" rumors that the killings might have something to do with voodoo or vampirism.
The next night, Adam visits the Barrio, asking to see the club's owner, Mr. Calderon [Vic Silayan]. He doesn't get very far with his cover about wanting to write a story about Maria's murder. Calderon agrees only to think about it. While discussing his article with Calderon, Adam's attention is drawn to the belly dancer Serena Brioso [Yvonne Nielson]. Later that night, as Adam prepares to sleep, he is attacked by a man with a machete. Hehehe. The man didn't know it, but the machete just killed Harvey the dummy. Adam was standing in the shadows with his loaded gun and killed the killer. A bit later, Adam goes for a walk and is confronted by a one-legged beggar named Herrera [Eddie Infante] who turns out to be Miguel's contact (and also the guy who took care of the machete-wielder's body). Herrera will be watching Adam and will never be too far away, he says. On his way back into the hotel, Adam sees Sylvia drive up. She tells him to get into her car and drives him several miles outside of the city, where she kisses him, then slaps his face and drives off, leaving Adam to walk back to his hotel. [This is payback for Adam stealing a kiss the night before.] On his walk back, Adam notices Theresa, a girl from the Barrio Club, being dropped off.
The next morning, Theresa turns up dead. [Clue: Both Teresa a d Maria were attacked by the same person, whose face looks like an advanced case of neurofibromatosis.] That evening, Adam returns to the Barrio Club to get an answer from Calderon regarding the article he wants to write. While they chat, Serena does her belly dance again. In the middle of the dance, however, she stumbles, feels her face, and runs out. [Clue: Serena is using the blood of the murdered girls to sustain her beauty.] Adam attempts to follow Serena but the club's bouncers toss him out.
The next time Adam goes to the Barrio Club, Serena takes him aside and asks him to meet her at the club the following evening when Calderon is planning to be away on business. Calderon is charming, Serena warns, but he can be strange and violent. While walking back to his hotel, Adam meets up with Herrera who informs him that another waitress (Elena Munoz) from the Barrio Club has disappeared. Adam informs Herrera about his planned meeting with Serena and tells him to relay the message to Miguelthat he should be ready to move when he gets a telephone call. When Adam returns to his hotel room, he is immediately aware that he's not alone. In the dark, he tackles the intruder. It turns out to be Sylvia bringing news from Miguel, who has been checking on Calderon's background. It seems that Calderon and Serena fled to Manila from Peru where Calderon was involved in the murder of a wealthy plantation owner. Calderon and Serena have been together for about three years. Now aware that she's in love with Adam,Sylvia boldly solicits a kiss.
The next evening, Adam meets Serena as planned. She tells him that Calderon is a maniac and is planning to kill both her and Adam. She asks Adam to meet her later that night, one hour after the club closes. In the meantime, she orders him a drink, which is served to him by none other than their newest waitress -- Sylvia. I wanted to help, Sylvia explains to Adam. Adam berates her for getting involved, not knowing that Serena is listening to their conversation. Sylvia calls Adam's attention to the armbands that Serena always wears. I saw them once in a London museum, Sylvia says. They're Aztec or Incan and very expensive.
Cut to Elena Munoz. She is currently tied to a table down in a cellar somewhere, and neurofibroma man is wielding a knife. He slits Elena's arms and collects the blood in a big cauldron. The cauldron then rotates in a circle, stopping at a chair where Serena is seated. Her face has turned haggard. She opens a locket, takes out a pinch of magical herbs, and tosses it in the blood. Immediately, a lot of fog covers her. When it clears, her face is young again.
An hour after the Barrio Club closes, Adam shows up as planned. Serena picks him up and drives him to her house. Adam pours himself a drink, but the liquor is drugged and he passes out, but not before Serena spins a tale of how Calderon killed his wife, killed Maria and Theresa, and threatened to kill her, too, should she ever leave him. When Adam comes to, Serena haughtily explains that she is a Golden Goddess, chosen by her people to be immortal, existing on the blood of young women. As sheraises a knife to kill Adam, Elena Munoz's father steps out from behind the tree. Serena runs, and Munoz cuts Adam free. Unfortunately, as Adam and Munoz make their getaway, Serena runs down Munoz and kills him. Adam is forced to make his way back to the club on foot, but not before he stops at a roadside stand and telephones Miguel.
Meanwhile, Sylvia was snooping around the club. She made her way down into the cellar where she was seen and caught by neurofibroma man. As he now prepares to slit her arms and collect her blood, Adam and Miguel break open the door. They shoot neurofibroma man, but he keeps coming. He tries to strangle both Adam and Miquel, but Herrera knocks him out with hiswooden leg. Adam and Miguel cut Sylvia free. Serena, who has been sitting in her chair waiting for blood, tosses the magical herbs into the cauldron of blood, but something goes wrong. First, she turns into an old Filippino woman, then she disintegrates into dust.
Epilogue: Miguel and Sylvia are saying goodbye to Adam at the airport. As a gift, Miguel presents Adam with a nicely-dressed and freshly-painted Harvey. Sylvia asks Adam whether he'll come back to Manila, and Adam answers by kissing her. [Original Synopsis by bj_kuehl.]