As World War II rages on, criminals try to take advantage of the resulting chaos. In Hastings, they aren't having much luck, thanks to Detective Chief Superintendent Christopher Foyle. As Foyle's son Andrew, a fighter pilot in the RAF, fights the enemy at war, Foyle battles the black market, profiteering and murder on the home front. He is dogged in his pursuit of justice, honest to a fault and frequently underestimated by his opponents. Following the war, Foyle takes on a new role as a senior intelligence officer, and he focuses his attention on the world of espionage in support of Britain's security and defence.