Mardi Gras Massacre is based on the movie that broke the barrier in showing gore on screen, the 1963 Blood Feast, but Massacre puts the gore in New Orleans and makes the ancient rituals Aztec. In this version of the same story, an Aztec priest goes around the world looking for prostitutes to sacrifice to Coatla, the Goddess of the Four Directions and Queen of Evil. Since the sacrifice involves removing the victim's heart, in one victim after the next, even the gore starts to match the tedium of the rest of the movie long before the final prostitute is dispatched.