J.J. is a beautiful American journalist who's sent to Brazil just as the famous Carnival begins, to investigate reports of brutal murders of street kids from favelas, the notorious Brazilian slums. The corrupt officials won't help, so through her producer's contacts she finds out where the next execution will happen on her own. Once there, she sees a vicious local crime boss called "Boca" ("Mouth"), short for his full street name--"Mouth of Gold", a nickname he got for having rows of golden teeth in his mouth, saving the children and killing the executioners. Since the corrupt local government and police have no intentions of stopping the killings, she tries to get close to Boca and convince him to help her with her story and save more kids. Surprisingly, he turns out to be very charismatic and, although he accepts her offer, he starts playing mind games with her. This, combined with his brutal, but intriguing, life story, exotic harem, and the Carnival's heated sexualized atmosphere, loosens J.J. up and she falls under his menacing, charming spell. That's when an overfriendly stranger, Jesse James Montgomery, a self-proclaimed CIA spook, warns her that Boca is a monster and that unless she comes to her senses she'll become his puppet and part of the city's underbelly. Convinced that Boca truly wants to help the poor children of favelas, she refuses to listen, and things soon escalate.