The last film in which Jack Hawkins' voice is heard. In subsequent films he would be dubbed by other actors due to his problems with throat cancer.
Zero Mostel and Akim Tamiroff were concurrently filming the comedy "Monsieur Lecoq " for Columbia and Carl Foreman. The movie however was cancelled due to " Poor weather conditions ", an industry euphemism for a troubled shoot.
Original director Elliot Silverstein, of " Cat Ballou " fame, quit after constant disagreements with star and co-producer Peter O'Toole. Silverstein reportedly claimed that he "wouldn't be a star's lackey", a remark which offended O'Toole greatly. He was replaced by Gordon Flemyng, who had just finished directing O'Toole in a television play.
The film was shot in the first part of 1967, but was not released until right at the end of 1968; it was a box-office and critical disaster and has been rarely seen since.