Allied spies and Nazi Agents insinuate themselves at a Scottish cottage (converted to a wartime hospital) with interests on an inventor's nearly perfected bomb sight.
| Directing | Anthony Asquith | Director |
| Writing | Geoffrey Kerr | Theatre Play |
| Writing | Anatole de Grunwald | Screenplay |
| Writing | J.O.C. Orton | Screenplay |
| Camera | Jack E. Cox | Director of Photography |
| Editing | R. E. Dearing | Editor |
| Production | Edward Black | Producer |
| Sound | Louis Levy | Music |
| Sound | Charles Williams | Music |
