 | Richard Todd als Edward Mercer |
 | Eva Bartok als Adriana Medova |
 | John Gregson als Renzo Uccello |
 | George Coulouris als Chief of Police Spadoni |
 | Margot Grahame als Rosa Melitus |
 | Walter Rilla als Count Boria |
 | John Bailey als Lieutenant Longo |
 | Sid James als Bernardo |
 | Martin Boddey als Gufo |
 | Michael Balfour als Moretto |
 | Sydney Tafler als Boldesca |
 | Miles Malleson als Grespi |
 | Eric Pohlmann als Gostini |
 | David Hurst als Minelli |
 | Raymond Young als Luigi |
 | Ferdy Mayne als Tio |
 | Jill Clifford als Renata |
 | Eileen Way als Woman Detective |
| Toni Lucarda als Nerva |
| Janice Kane als Ninetta |
 | Meier Tzelniker als Mayor of Mirave |
| Betty E. Box als Woman Next to the Factory Tour Guide (Uncredited) |
 | Victor Harrington als Bystander (Uncredited) |
| Ralph Thomas | Director |
| Victor Canning | Novel |
| Victor Canning | Screenplay |
| Betty E. Box | Producer |
| Earl St. John | Executive Producer |
| Ernest Steward | Cinematography |
| Gerald Thomas | Editor |
| George Provis | Art Direction |
| Yvonne Caffin | Costume Design |
| Jack N. Green | Third Assistant Director |
| Ernest Gasser | Makeup Artist |
| Stella Rivers | Hairstylist |
| Douglas Peirce | Production Manager |
| Peter Bolton | Assistant Director |
| John Dennis | Sound Recordist |
| Gordon K. McCallum | Sound Mixer |
| Peter Seabourne | Sound Editor |
| H. A. R. Thomson | Camera Operator |
| Cornel Lucas | Still Photographer |
| Yvonne Caffin | Costume Supervisor |
| Muir Mathieson | Conductor |
| Tilly Day | Continuity |
| Arthur Alcott | Production Controller |
| Nino Rota | Original Music Composer |
| Ernest Steward | Director of Photography |
| Jim Ware | Second Assistant Director |
| Robert Cartwright | Draughtsman |
| Roy Dorman | Draughtsman |
| John Gow | Draughtsman |
| Iris Newell | Assistant Art Director |
| Roy Walker | Draughtsman |
| Charles Squires | Assistant Sound Editor |
| John Alcott | Clapper Loader |
| Reginald H. Morris | Focus Puller |
| Peter Boita | First Assistant Editor |
| Maurizio Lodi-Fè | Location Manager |
| Fanya Fisher | Production Secretary |
