 | Yul Brynner als Victor Fabian |
 | Kay Kendall als Dolly Fabian |
 | Geoffrey Toone als Dr. Richard Hilliard |
 | Maxwell Shaw als Jascha Gendel / Grisha Gendel |
 | Mervyn Johns als Mr. Alonzo Wilbur Jr. |
 | Martin Benson als Luigi Bardini |
| Harry Lockart als Chester |
 | Gregory Ratoff als Maxwell Archer |
 | Shirley Anne Field als Angela Hooper |
 | Colin Drake als Doctor (uncredited) |
 | Andrew Faulds als Interviewer (uncredited) |
| Barbara Hall als Secretary (uncredited) |
| Grace Newcombe als Mrs. Wilbur (uncredited) |
| Stanley Donen | Producer |
| Hubert de Givenchy | Costume Design |
| Stanley Donen | Director |
| Georges Périnal | Director of Photography |
| Harry Kurnitz | Theatre Play |
| Harry Kurnitz | Screenplay |
| Jack Harris | Editor |
| Alexandre Trauner | Production Design |
| Eric Allwright | Makeup Artist |
| Jean Paul Ulysse | Makeup Artist |
| Julien Derode | Production Manager |
| Christian Ferry | Assistant Production Manager |
| Paul Feyder | Assistant Director |
| Joseph de Bretagne | Sound Engineer |
| Stanley W. Sayer | Camera Operator |
| Hubert de Givenchy | Wardrobe Supervisor |
| Roger Dwyre | Assistant Editor |
| Christian Ferry | Location Manager |
| Lucie Lichtig | Script Supervisor |
| Maurice Binder | Title Designer |
| Muir Mathieson | Conductor |
| Franz Reizenstein | Music Arranger |
| Muir Mathieson | Music Arranger |
| Joan Joseff | Other |
