The film is set in a noirish smog-shrouded London and briefly in Brittany, France, and combines the genres of mystery, thriller, crime and drama.

[4] Having been sent a picture of her husband, a war hero reported missing in action in France, Meg Elgin, now engaged to Geoffrey Leavitt, is led to believe he is still alive and arranges a meeting at a London railway station.

The men had been led to believe that Elgin knew about secreted treasure in a house in Brittany which he owned before the war, and they are desperate to get their hands on it.

Leavitt returns to Meg and together they head to Brittany to find the treasure, having learned of its location from a message left by Major Elgin.

Roy Ward Baker was offered the job of directing by producer Leslie Parkin, who worked with him on Morning Departure.

"[5] The Monthly Film Bulletin wrote: "The opening sequences of this adaptation of Margery Allingham's enjoyably confused novel are full of promise.

But with the appearance of the homicidal Jack Havoc, following a long and effective build-up, the film begins its marked deterioration into the commonplace.

Regrettably, Tony Wright fails to convey the raw, exposed neurosis of the character, investing the part with more brawn than psychopathic insight.

The rest of the playing is also highly variable, although there are several recognisable Allingham characters, notably the Scotland Yard men of Alec Clunes and Christopher Rhodes and the sinister Mrs. Cash, portrayed with considerable relish by Beatrice Varley.

"[7] Variety called it "An intriguing, nearly plausible Screenplay has been made... With a sterling cast, and not over complicated plot, the result is good general entertainment... Tony Wright is making his mark in the cold killer type of roles and this one fits him like a glove.