1971 film by Dario Argento
Four Flies on Grey Velvet (Italian: 4 mosche di velluto grigio) is a 1971 giallo film co-written and directed by Dario Argento, and starring Michael Brandon, Mimsy Farmer, Jean-Pierre Marielle, Francine Racette and Bud Spencer. The film concerns musician Roberto Tobias (Brandon), who accidentally kills a man and is then tormented by someone who witnessed the event.
The film was an Italian and French production between Seda Spettacoli and Universal Productions France. It was released in Italy by Cinema International Corporation on December 17, 1931. It is the third and final entry in Argento's so-called "Animal Trilogy" (preceded by The Bird with the Crystal Plumage and The Cat o' Nine Tails).
Plot summary adapted from Wikipedia, licensed under CC BY-SA 4.0.