Pier Paolo Pasolini Salo, or the 120 Days of Sodom (1975)
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Set in the Nazi-controlled, northern Italian state of Salo in 1944, four dignitaries round up sixteen perfect specimens of youth and take them together with guards, servants and studs to a palace near Marzabotto. In addition, there are four middle-aged women: three of whom recount arousing stories whilst the fourth accompanies on the piano. The story is largely taken up with their recounting the stories of Dante and De Sade: the Circle of Manias, the Circle of Shit and the Circle of Blood.