The film's plot follows a serial killer roaming the streets of New Orleans, Louisiana, sacrificing women to an Aztec goddess.

[5] In New Orleans, Louisiana, a dapper and mysterious middle-aged man named John arrives at a bar searching for the "evilest" prostitute he can take home.

He begins massaging her and then ties her to the table and eviscerates her, removes her heart, and offers it on an altar in an Aztec sacrifice to the goddess Coatl, the "queen of evil."

When questioning other local prostitutes, Hebert meets Sherry and discovers from her that the man whom Shirley had left with the night she died wore an unusual gold ring.

Meanwhile, Frank's superiors urge him and Mayer to prevent the murders from being publicized in fear that it will hamper the impending Mardi Gras celebration.

At a different club, he attempts to court another dancer but is confronted in the street by her pimp, whom John brutally stabs to death before fleeing.

Meanwhile, John meets Joe, a bartender, and offers him a large sum of money for three prostitutes for Fat Tuesday, during which he plans to provide three women to Coatl at once.

John flees via a fire escape and leads Frank and Mayer on a chase through the French Quarter, ending at the Governor Nicholls Street Wharf.