Mortal Sin (1970)

The eccentric members of a wealthy Brazilian family each go through personal torment, debauchery and intense guilt in this symbolic and gory film. The father has made a fortune in the slaughterhouse business and ignores the feelings of his wife and his workers. He frequents a mulatto woman, who is always seen naked. His daughter and her friend act on their lesbian fantasies before her friend marries her brother. An elderly aunt seduces the brother before she drowns herself in the swimming pool. His lesbian sister shoots the girl, and the boy incestuously attacks his mother. When the mother threatens to leave, the father begs for her to stay and continue the hollow charade of their marriage for the sake of social appearances. The father grovels before his mistress after his daughter slashes her wrists. Any comparison between this dysfunctional family, the Manson family, and Shelley Winters' sick Barker brood in Bloody Mama is all an unfortunate artistic coincidence.