A physicist finds himself drawn into an investigation to track down a spy at his research station.
| Directing | Ronald Kinnoch | Director |
| Production | Ronald Kinnoch | Producer |
| Sound | Albert Elms | Music |
| Production | Douglas Hermes | Production Manager |
| Writing | Brian Clemens | Screenplay |
| Costume & Make-Up | George Frost | Makeup Artist |
| Costume & Make-Up | Doris Pollard | Hair Setup |
| Editing | Peter Mayhew | Editor |
| Camera | Ernest Day | Camera Operator |
| Writing | Ronald Kinnoch | Screenplay |
| Art | Bill Constable | Set Designer |
| Camera | John Winbolt | Camera Operator |
| Production | Richard Gordon | Executive Producer |