The Bird with the Crystal Plumage was the great Dario Argento's directorial debut as well as one of his best plotted films. This was the first of his "Animal Trilogy" along with Cat o' Nine Tails and Four Flies on Grey Velvet shortly thereafter. All of these films were score by the man himself, Ennio Morricone. To put soundtrack in perspective I feel its important to point out the impact he made on the whole of film. When horror was bogged down with cliche, Morricone broke the mold, much the same as he did with the western genre on his DOLLAR scores.
Instead of the the overuse of strings, Morricone's approach was drug-addled experimental jazz. In the violent scenes he trademarked his placement of lullabyes and heavy breathing that became a oft-imitated standard in horror. As simple as these ideas sound, they are incredible unsettling and very creepy in the context of the film.
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