It goes without saying that by this time detective stories and murder mysteries arrive with a great deal of thespian baggage. Any filmed story that depends heavily on plot with an emphasis on finding all the clues along the way to a revealing conclusion must by its very nature owe much to established convention. Thus a review or critique seeking to find unique properties must needs look to elements other than plot. In this case one comes across excellent production values, superb acting, and an historical feel that avoids 21st century sentiment.
To anyone who lived through the time in question, the notion that people behave differently in times of national peril is a given. Yet there was always underlying the stress and uncertainty as to mere survival an everyday kind of dealing with affairs such as buying and selling goods, attending to civic duties, looking out for one's family, and avoiding the tax man. The role of a policeman was in that sense highly valued, as this series seeks to demonstrate. Even during blackouts and air raid drills, we still had to depend on ordinary policemen to maintain order. And things like rationing and price controls lent themselves quite naturally to crimes such as profiteering and, to some extent, episodes of violence that are the stuff of all murder mysteries.
Foyle as created by the writer was trapped by circumstance as so many of us were in roles on the home front. As one of the episodes points out, he was prevented from taking a direct role in military affairs by way of having made enemies of influential officers in the course of pursuing his police investigations. The scope of this series is broad, much more than can be conveyed in any one episode. I was particularly impressed with how the father and son relationship, appropriately played by Kitchen and Ovenden (who even bear a physical resemblance to each other), evolve over several episodes.
Do by all means find a way to buy or rent the whole series so as to appreciate more than this or that plot. Some of them are a little thin and formulaic without that spectrum.