The gimmick of the show - you want to call it that - is that it's wartime Britain, 1939-45, and superintendent Foyle (who'd rather be actively serving) is assigned to criminal cases, on the homefront. These, given the genre, are murder mysteries, but the war is always present, in the foreground or just over the horizon.
The canvas is quite broad, although the stories generally resolve themselves in the homely and familiar, the domestic disturbances of daily life. The constants, an illicit affair or an unwanted pregnancy, envy, greed, wrath, and pride, are the usual suspects, but they often involve wider anxieties: the German bombing raids, fears of an impending invasion, rationing and the black market, war profiteers, isolationists and Nazi sympathizers, spy-hunters from Special Branch, the code-breaking at Bletchley, the rescue from Dunkirk, these have all figured in the plotlines. Nor is it window-dressing. The war becomes a character.
Foyle is played by Michael Kitchen, one of those actors you sort of remember, but can't quite place the name. I first noticed him in TO PLAY THE KING, the sequel to HOUSE OF CARDS - the original, with Ian Richardson. Kitchen has a lived-in face. He makes Foyle seem approachable, but there's a weariness, something held in reserve, an inner, or even inward, person. Once in a while, the well-mannered mask slips, and the steel shows through.
An interesting director's device I noticed. They use a lot of close-ups, which is common in television, but in this case, there are often long, very tight shots of Foyle, where you see only a slight facial movement, a tug of his mouth, or his eyes downcast, and then an up-from-under glance. The visual equivalent of Columbo's near-exit line, "Oh, just one more thing - "
When you do period drama, it's more than the vintage cars, or everybody wearing hats. It's about the psychological environment, the circumstance, the way people think. I know this myself, from writing the Mickey Counihan stories, which take place in late 1940's postwar New York, and Janice Law, to take a not-so-random example, is careful in her Francis Bacon novels not to fall into anachronism, meaning her world (and Bacon's) is
pushing up against the Modern, but it hasn't quite arrived, yet. It's just around the corner. This is the background music of FOYLE'S WAR. Nobody knows for sure that Hitler's going to be beaten, or whether England will survive. They go about their business with possible calamity waiting in the wings, but they keep their wits, and their common decency. Foyle is heroic, not because he has extraordinary powers, or sees behind the curtain, but simply because he does his job, in a trying time. He rises to the occasion. This is the persistence of the everyday. Life, in its messy particulars, stumbles ahead. The war effort is one thing, just keeping your head above water is another.