It's said that the Manson murders are what finally killed the 60's. They were a cultural event and the entire affair has become a monolithic legend, shot through with tales of drugs, ritualistic sacrifice, the occult, hippiedom, counter-culture, communal cults, and Hollywood decadence; you can see its echoes in films of the time and long after. These are those films. Some directly reference Manson, some hint at him, some simply have themes and threads that connect back to the idea of hippie cult slaughter and the dark side of the era. These are the films that marked the death of idealism, and the ones that came after.