'Belle De Jour'
Trapped in a sexless marriage and rolling around in fantasies of BDSM, a housewife, Séverine, decides to spend her afternoons as a prostitute to fulfill her needs and desires. While it might not sound that scandalous, the movie, which is French, came out in 1967. Making it not just sexy for the time, but way, way ahead of its time in regards to tackling the BDSM kink.