and Wallach subsequently sued. Leone was initially dissatisfied with Steiger's performance in that he played his character as a serious, Zapata-like figure. As a result, tensions rose between Steiger and Leone numerous times, including an incident that ended with Steiger walking off during the filming of the scene when John destroys Juan's stagecoach. However, after the film's completion, Leone and Steiger were content with the final result, and Steiger was known to praise Leone for his skills as a director. Filming Exterior filming mostly took place in Andalusia, southern Spain. Some of the locations used previously featured in Leone's Dollar Trilogy films; for example, the Almería Railway Station, used for the train sequence in For a Few Dollars More, returns in this film as Mesa Verde's station. The flashback scenes with Sean and friends were shot in Ireland at Howth Castle in Dublin, and Toner's Pub on Baggot Street, Dublin. As filming progressed, Leone modified the script: as he did not originally plan on directing Duck, You Sucker, he thought the script was "conceived for an American filmmaker". Duck, You Sucker! was one of the last mainstream films shot in Techniscope. Music 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. Themes Despite the politically charged setting, Duck, You Sucker! was not intended as a political film: Leone himself said that the Mexican Revolution in the film is meant only as a symbol, not as a representation of the real one, and that it was chosen because of its fame and its relationship with cinema, and he contends that the real theme of the film is friendship: Another theme is amoral non-engagement: Juan is very