El sádico de Notre-Dame

If you manage to find the fully uncut version of "Exorcism", then you have "The Sadist of Notre Dame". This has always been one of my favorite Jess Franco achievements. It's obviously not on par with his true classics like "The Awful Dr. Orloff", "Faceless", or "Diabolical Dr. Z", but it's nevertheless a tense and brutal shock-tale. It also features Jess Franco's biggest (and best) acting performance, as the mentally unstable ex-priest Mathis Laforgue who recently escaped from a psychiatric clinic and now dwells the streets of Paris. He sees himself as a redeemer, sent by God to wipe out all that is impure. Laforgue kills prostitutes, horny teenagers, and random partygoers, all whilst claiming he's saving their souls. Always liked this one because it is a cruel exploitation story with nevertheless an uncannily realistic ambiance. Paris is perhaps considered the most beautiful city in the world, but here you only see eerie dark alleys, freaks & outcasts, vile acts of torture and mutilation, and pure perversion.