Bloody Mama (1970) on Netflix

A psychological gangster film based on fact. Machine gun totin' Ma Barker lead her family gang (her sons) on a crime spree in the Depression era. Her loyal brood have every perversion imaginable. The sadistic Herman sleeps with his Ma. When Fred Barker is released from prison, he brings home his cell mate/lover Kevin Dirkman, who also sleeps with Ma, much to Fred's chagrin. Lloyd Barker is a spaced-out drug addict who sniffs glue if nothing better is around. Ma kidnaps happy-go-lucky millionaire Sam Adams Pendlebury and holds him for ransom. Arthur Barker - Ma's wallflower son - and Herman's hooker lady friend Mona Gibson also figure in the story. The bloody finale is virtually choreographed and a visual stunner. Filmed in the Ozarks.