Charlie's Angels: Angels on a String

"Angel on a String" is the fifteenth episode of season one of the action/mystery television series Charlie's Angels. It was directed by Phil Bondelli and written by Robert Earll. It first aired on ABC on January 19th, 1977. In this episode, a young woman hires the Angels to look into the disappearance of her half-sister whom she believes had been arrested for drug trafficking. The Angels have themselves deliberately arrested and taken to a women's correctional facility where they discover a corrupt sheriff is using the prison to force it's inmates into a world of prostitution.