Last House on the Left is a revenge

Last House on the Left is a revenge flick sure, but it's also study on pure maternal instinct and revenge.

Two cute girls, teenagers are hanging out, find themselves in the wrong place at the wrong time when they go to the apartment of a boy named Justin (Spencer Treat Clark) to smoke some pot and chill out, when his family comes back who are wanted in the connection with some local murders. Now they can't let the girls go. From there things get steadily worse until the girls are left brutalized.