Mi caro assassino (1972) by Tonino Valerii
aka: My Dear Killer

The never resolved case of a kidnapped and later killed girl Stefania Moroni (Lara Wendel) warms up again, when one day private investigator Paradisi is found decapitated by a digger at a building pit close to the tragic location. A tough case for Inspector Luca Peretti (George Clinton), as his witnesses – as usually – get killed one after the other and the only clue seems to be hidden somewhere at or around the crime scene. But where?

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