Trailer
Images
 | Tony Britton as Dr. Robert Marriott |
 | Virginia Maskell as Dr. Lucy Byrne |
 | Ian Bannen as Alan Andrews |
 | Kenneth Griffith as Dr Shole |
 | Peter Cushing as Professor Sewell |
 | Thorley Walters as Special Agent Prince |
 | Donald Pleasence as Parsons, alias Bill Brown |
 | Spike Milligan as Arthur, lab orderly |
 | Raymond Huntley as Sir George Gatting the Minister of Defense |
 | Sam Kydd as Slater |
 | Anthony Booth as Parkin |
 | Basil Dignam as Dr Childs |
 | Brian Oulton as Director |
 | Robert Bruce as Levers |
 | John Payne as Iverson |
| Bruce Wightman as Phil the Barman |
 | Geoffrey Bayldon as Rosson |
 | Andre Charisse as Heller |
 | Ian Wilson as Pin Table Man |
 | Margaret Lacey as Prince's Secretary |
 | Murray Melvin as Teddy Boy |
| Directing | |
| Roy Boulting | Director |
Writing | |
| Roy Boulting | Writer |
| Nigel Balchin | Novel |
| Nigel Balchin | Screenplay |
Editing | |
| John Jympson | Editor |
Art | |
| Albert Witherick | Art Direction |
| Peter James | Set Decoration |
Directing | |
| John Boulting | Director |
Camera | |
| Mutz Greenbaum | Director of Photography |
| Laurie Ridley | Still Photographer |
Production | |
| John Boulting | Producer |
| Roy Boulting | Producer |
Costume & Make-Up | |
| Anne Box | Hairstylist |
| Freddie Williamson | Makeup Artist |
Production | |
| Philip Shipway | Production Manager |
Directing | |
| Basil Rayburn | Assistant Director |
Crew | |
| Alan Evans | Scenic Artist |
Sound | |
| George Stephenson | Sound Mixer |
Camera | |
| Peter Allwork | Camera Operator |
| Gerry Anstiss | Assistant Camera |
