I consider myself a pretty casual Argento fan - stuff like "Susperia" and "Deep Red" ranking high on my respective list of favorite Italian horror and the giallo genre, itself, I typically enjoy - but "Four Flies on Grey Velvet" didn't do much for me... It's your fairly standard "giallo" set-up: a series of murders surrounding this one central person who just so happened to get mixed up with the wrong individual at some point and it's now biting them in the ass. In the case of this particular musician who accidentally stabbed some guy who was apparently stalking him - he can't seem to shake this latest pursuer with his/her creepy doll mask and vicious compulsion to beat people's heads in with a stylish POV proficiency. It's a stirring blackmail situation that calls for a not-so proficient homosexual private investigator and a couple winos...
I didn't hate the movie, it just didn't fulfill my need for gore and taut female bodies shedding their attire for no decipherable reason. I will say, "Four Flies on Grey Velvet" had one cool climax involving a pretty neat slow-motion car crash. Like the majority of giallo endings, the twist involving the 'motive explanation' - was a bit 'lost in the shuffle' and I didn't find it easily discernible in contrast with everything that had previously transpired, but it still works if you just accept it... I also liked that high-tech interjection of retina-reading. Very random and gratuitously "sciencey" for an Argento flick! Still, the flick needed more brutality, nudity, and creepiness to make it stand out...