 | David Knight als Ted Hutchens |
 | Odile Versois als Anna Szobek |
 | Theodore Bikel als Joseph |
 | David Kossoff als Geza Szobek |
 | Joseph Tomelty als Moffatt |
 | Paul Carpenter als Gregg Pearson |
 | Peter Illing als Dr. Weissbrod |
 | John McLaren als Col. Margetson |
 | Bernard Rebel als Stefan |
 | Jill Adams als Judy (uncredited) |
 | Robin Bailey als Thomas Cook cashier (uncredited) |
 | Dora Bryan als Switchboard Operator (uncredited) |
 | Peter Dyneley als Regan (uncredited) |
 | Dwight D. Eisenhower als Himself, in photo (uncredited) |
 | Percy Herbert als Richards (uncredited) |
 | Sam Kydd als Driver, Embassy car JAK711 (uncredited) |
 | Victor Maddern als Sailor (uncredited) |
 | Betty Marsden als Mrs. Forrester (uncredited) |
 | Aubrey Mather als Waiter (uncredited) |
 | Joan Sims als Telephone Operator, American Embassy (uncredited) |
 | Russell Waters als Counterman (uncredited) |
| Anthony Havelock-Allan | Producer |
| Robin Estridge | Writer |
| Anthony Asquith | Director |
| Frederick Wilson | Editor |
| George Tabori | Story |
| Jack Asher | Director of Photography |
| Benjamin Frankel | Original Music Composer |
| Denis Holt | Production Manager |
| Robert Asher | Assistant Director |
| John Box | Art Direction |
| Yvonne Caffin | Costume Design |
| Waleen Whitworth | Hairdresser |
| Roger Cherrill | Sound Editor |
| Gordon K. McCallum | Sound Mixer |
| John W. Mitchell | Sound Recordist |
| H. A. R. Thomson | Camera Operator |
| Benjamin Frankel | Conductor |
| Kathleen Hosgood | Continuity |
| Arthur Alcott | Production Controller |
