My daughter and son-in-law saw the movie. They commented that it was hard to follow at times. Much like other Quentin Tarantino films.
also before one sees they need to know the general background
who was Sharon Tate, Roman Polanski, Charles Manson, hippie communes
1960s Hollywood, what is spaghetti western etc
when they had a billboard for the TV show "Combat" that was classic 1960s shit right there! I loved that - it is the little things