13. Last House On The Left (1972)
Two beautiful young girls - Mari and Phyllis - have the misfortune to run into a gang of fugitive criminals when they are trying to score cannabis. The thugs are led by the vicious and sadistic Krug (David Hess) who has gotten his son Junior hooked on heroin so he can control him. There is also slimy pervert Weasel and degenerate wild woman Sadie. They kidnap the girls and torture and humiliate them, then inexorably rape and kill them. They show up, posing as respectable people to Mari's house nearby. Eventually through a series of circumstances, Mari's parents figure out the trio have killed their daughter and Phyllis. They go about planning their revenge and it is castration and chainsaws a go go. The torture scene of the girls is extremely repellant - the crew getting one of them to wet herself and forcing them to get lesbian with each other. And this is before they rape and kill them. Krug has to be one of the most repellant villains in the history of cinema - engineering and encouraging his own son's suicide. At the end we don't feel that Mari's parents are any better for killing the thugs. There is no sense of victory and it makes the violence of the film even more repellant.