There has been a lot written about this movie; slammed as vile and depraved upon release, and leading to the premature death of one of Britain's greatest ever filmmakers, it, like Hammer's Dracula, has been reassessed as a masterpiece of British cinema. Martin Scorsese has just completed a remastering of the original print, which is now on re-release (in London at least!).
A couple of sample stories:
http://www.guardian.co.uk/film/filmblog/2010/nov/16/peeping-tom-pornography-press-camera
http://www.guardian.co.uk/culture/charlottehigginsblog/2010/nov/09/martin-scorsese-peeping-tom
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