 Two teenage girls, Mari and Phylis, go to the "big city" to celebrate Mari s 17 birthday at a rock concert. Before the concert, they go on a careless hunt for some pot only to end up getting raped, humiliated, and eventually killed by four psychopaths. When the killers seek refuge at one of the girls  house by mistake, the parents find out just what happened to their little girl. Then they seek revenge.