Gary Cooper was very pleased with his performance and very disappointed that the majority of critics thought him miscast due to his age. Indeed, the film's box-office failure was largely attributed to his being considered too old to play Audrey Hepburn's lover. In April 1958 he had a full facelift and other cosmetic surgery, but the procedure was largely unsuccessful.
The movie was a critical and commercial failure on release. Many critics felt that 55-year-old Gary Cooper was too old for the part, and ought to have turned it down, as Cary Grant had.
In the scene where Frank and Ariane have their first tryst, the last musician who runs into the hotel room is Billy Wilder with a hat pulled over his eyes.
A line was dubbed into the release print to dispel the impression that Audrey Hepburn's and Gary Cooper's characters have sex in their many afternoon meetings in his hotel room. As he is moving out of frame in Maurice Chevalier's office, Cooper obviously replaces a different filmed line in voiceover, and says, "I can't get to first base with her." This appears to be an effort at self-censorship, given the clear implications of sexual intimacy that come before this scene.