Last House On The Left
A defining moment in the evolution of American horror. But more importantly, the source of Mark's story about his efforts to have the film passed uncut, which worked so spectacularly badly that the initial 16 seconds of cuts the BBFC had wanted were doubled.
Very attentive readers of this wiki will notice that there is also an article about The Last House On The Left which has exactly the same story on it. Probably someone will sort this out. But for now it serves as a summation of the confusion about the film's title which, aptly enough, gets a whole page in Mark's book Hatchet Job.