Il était une fois la révolution
The musical score for "Duck, You Sucker!" was composed by Ennio Morricone, who collaborated with Leone in all his previous projects as a director with the exception of his debut, "The Colossus of Rhodes". Elvis Mitchell, former film critic for "The New York Times", considered it as one of Morricone's "most glorious and unforgettable scores". He also sees "Invention for John", which plays over the opening credits and is essentially the film's theme, "as epic and truly wondrous as anything Morricone ever did". A soundtrack album was released in the United States in 1972, and many tracks can be found in Morricone's compilation albums. Music was recorded in April 1971 and second recording sessions in August/September 1971. A 35th anniversary OST was issued in 2006 with previously never released recording session and alternate takes.