Harry is a married writer who has an affair with a woman whose husband knows that she is unfaithful. As a result of his work, Harry has trouble distinguishing between fantasy and reality leaving us to wonder whether the affair is real or just a figment of Harry's imagination.
| Production | Jud Kinberg | Producer |
| Writing | Nicholas Mosley | Novel |
| Directing | John Frankenheimer | Director |
| Sound | Antoine Petitjean | Sound |
| Camera | Claude Renoir | Director of Photography |
| Writing | Nicholas Mosley | Screenplay |
| Production | Robert Bradford | Executive Producer |
| Sound | Michel Legrand | Music |
| Editing | Albert Jurgenson | Editor |
| Art | Alexandre Trauner | Production Design |
| Art | Albert Volper | Set Decoration |
| Costume & Make-Up | Jacques Fonteray | Costume Design |
| Costume & Make-Up | Alex Archambault | Hairstylist |
| Costume & Make-Up | Monique Archambault | Makeup Artist |
| Production | René Fargeas | Unit Manager |
| Production | Lucien Lippens | Unit Manager |
| Production | Georges Vallon | Production Manager |
| Directing | Bernard Stora | Assistant Director |
| Sound | Jacques Carrère | Sound Mixer |
| Sound | Renée Deschamps | Sound Effects |
| Camera | Daniel Braunschweig | Key Grip |
| Camera | René Chabal | Assistant Camera |
| Camera | Vladimir Ivanov | Camera Operator |
| Lighting | Bouhamdi Lyamani | Electrician |
| Camera | Charles-Henri Montel | Camera Operator |
| Camera | Vincent Rossell | Still Photographer |
| Costume & Make-Up | Deborah Dixon | Wardrobe Supervisor |
| Editing | Catherine Kelber | Assistant Editor |
| Directing | Lucie Lichtig | Script Supervisor |
| Art | Jean Fouchet | Main Title Designer |