The film was first envisaged as a starring vehicle for Marcello Mastroianni and Kim Novak with Frank Perry directing.
Michel Legrand composed the first score for this film, but it was rejected in favor of a score by John Barry, aided by Don Walker. When it was first aired on U.S. television, the CBS network had Barry and Walker's score replaced with a completely new score by Stu Phillips.
Sidney Lumet was originally very defensive of his film, following its disastrous reception at the Cannes Film Festival, but, in later years, claimed he had only agreed to do the movie for a chance to work with Carlo Di Palma. Lumet had had problems earlier in his career with color in film and wanted to learn from the DP of Red Desert (1964). Source: Making Movies by Lumet.