This is rather an intriguing wartime drama - not so much because of the mystery itself, that's all pretty routine - more because of the subject matter. Richard Greene is journalist "Bob Randall" who comes back from the Dunkirk evacuation bent on investigating the pacifists in Britain who may well prove to be an easy target for Nazi fifth columnists. Together with fellow reporter "Carol Bennett" (Valerie Hobson) they start to dig and soon realise just what could be at stake! It's a far grittier depiction than many, people genuinely fearful in underground stations whilst the blitz roars on overhead does elicit a sense of their predicament and of the risks of defeat that may well have been felt in London in 1942. There's a solid supporting cast to keep the mystery bubbling along, but it does at times resemble a far more potent - almost propagandist - warning against appeasement than a movie!