Leading man Michel Piccoli plays Pierre, a young musician who briefly catches sight of a beautiful woman dressed in blue and soon spends all of his time trying to track her down. After roaming the streets of Paris in search of the mystery woman, he recruits an old friend to help find her.
| Directing | Michel Deville | Director |
| Camera | Claude Lecomte | Director of Photography |
| Editing | Raymonde Guyot | Editor |
| Writing | François Boyer | Writer |
| Writing | Michel Deville | Writer |
| Writing | Léo L. Fuchs | Writer |
| Production | Léo L. Fuchs | Producer |
| Sound | André Girard | Music |
| Costume & Make-Up | Simone Baron | Costume Design |
| Costume & Make-Up | Paulette Breil | Costume Design |
| Costume & Make-Up | Marie-Louise Gillet | Makeup Artist |
| Sound | André Hervée | Sound |
| Sound | Françoise London | Sound Editor |
| Sound | Gérard Manneveau | Sound Assistant |
| Sound | Daniel Couteau | Foley Artist |
| Sound | Alex Pront | Sound Mixer |
| Directing | Monique Herran | Script Supervisor |