| Person | Type | Job | Role(s) |
|---|---|---|---|
 Ivan King | Crew | Art | Art Direction |
Jack Davies | Crew | Writing | Screenplay |
 Mario Zampi | Crew | Directing | Director, Producer |
Michael Pertwee | Crew | Writing | Screenplay |
 Stanley Black | Crew | Sound | Original Music Composer |
Stanley Pavey | Crew | Camera | Director of Photography |
Giulio Zampi | Crew | Editing | Editor |
 Anton Diffring | Cast | Actor | Border Police GDR (uncredited) |
Bernard Rebel | Cast | Actor | Trubiev |
 Charles Goldner | Cast | Actor | Gaston |
 Christopher Lee | Cast | Actor | Russian Agent (uncredited) |
 David Hurst | Cast | Actor | Deutsch |
 Edwin Styles | Cast | Actor | Barworth Superintendent |
 Eleanor Summerfield | Cast | Actress | Cecilia |
Ernest Jay | Cast | Actor | Professor Layton |
Fred Berger | Cast | Actor | Russian Doctor |
 Frederick Leister | Cast | Actor | Prime Minister |
 Frederick Valk | Cast | Actor | Rakov |
 Geoffrey Sumner | Cast | Actor | Pike |
 George Cole | Cast | Actor | George Archibald Potts |
 Gerard Heinz | Cast | Actor | Russian Director of Plant |
 Gibb McLaughlin | Cast | Actor | Schoolmaster |
Guido Lorraine | Cast | Actor | 1st M.V.D. |
 Hal Osmond | Cast | Actor | Jersey Waiter |
 Henry Hewitt | Cast | Actor | Minister of Health |
 Ina De La Haye | Cast | Actress | Madame |
 Irene Handl | Cast | Actress | Mrs. Tidmarsh |
 Kynaston Reeves | Cast | Actor | Barworth Director |
 Martin Boddey | Cast | Actor | Russian Security Officer |
 Michael Balfour | Cast | Actor | Jersey Sailor |
 Michael Medwin | Cast | Actor | Smedley |
 Nadia Gray | Cast | Actress | Tania |
 Olaf Pooley | Cast | Actor | Roblettski |
 Oskar Homolka | Cast | Actor | Zekov |
Phyllis Morris | Cast | Actress | Mrs. Tweedy |
Reed De Rouen | Cast | Actor | 1st U.S. Soldier |
 Richard Marner | Cast | Actor | Russian Sentry |
 Richard Wattis | Cast | Actor | Barnes |
 Ronald Adam | Cast | Actor | Barworth Controller |
 Ronnie Stevens | Cast | Actor | Aubrey |
 Terence Alexander | Cast | Actor | 2nd M.V.D. |
 Tim Turner | Cast | Actor | 1st Reporter |
 Victor Maddern | Cast | Actor | British N.C.O. |
Walter Horsbrugh | Cast | Actor | 1st Cabinet Minister |
 Wilfrid Hyde-White | Cast | Actor | Sir Hubert Wells |
 Willoughby Gray | Cast | Actor | British Officer |
Myrtle Reed | Cast | Actress | Jersey Air Hostess |
Anthony Shaw | Cast | 2nd Cabinet Minister | |
Johnny Catcher | Cast | 2nd U.S. Soldier | |
| Person | Type | Job | Role(s) |
