Four Flies on Grey Velvet

I was watching the X-Files episode with Peter Boyle as the insurance agent of death, and there was a scene that reminded me of one of Dario Argento's first movies: 4 mosche di velluto grigio (1971) . Actually, the X-Files scene made a reference or, perhaps, paid homage to Dario Argento's plot device: essentially, a murdered person has the image of his murderer imprinted on his retinas.

"Four Flies on Grey Velvet" combined humor, horror, and mystery into an entertaining and fun package, much the same way that X-Files would years later. As a bonus Bud Spencer played Godfrey with the emphasis on the first syllable, God.