The arrest of a young girl on a sabotage charge brings Foyle into contact with a group of English Nazi sympathizers. Shots are fired at the group's charismatic leader, but it is the hotel owner who dies. Foyle investigates the murder and uncovers a plot to smuggle a vitally important letter to the enemy.

A conscientious objector dies in police custody, setting in motion a series of suspicious deaths and a complicated puzzle for Foyle. When Foyle has pieced together the truth, the entry of Italy into the war engulfs a close friend in tragedy.

September 1940. Sam's boarding house is bombed and valuables disappear, alerting Foyle to an organized ring of looters. After the father of one of the suspected looters is found dead on the beach, Foyle and Milner's investigation leads them into conflict with British efforts to secure the donation of American Aid and the crucial start of Lend-Lease in the war.

September 1940. As Foyle's son Andrew takes to the skies for dangerous sorties over Germany, Sam goes undercover at a fuel depot to help crack an illicit fuel racket. Sexual indiscretions and racketeering plus links to Andrew combine to make this a delicate case for Foyle.

February 1941. Foyle investigates strange happenings at a manor house that has been converted into a burn unit for RAF pilots. The brilliant but unconventional surgeon who heads the unit has drawn the ire of his military superiors for disregarding regulations that conflict with patient welfare.

April 1941. Foyle and Milner capture two German soldiers who survive the crash landing of their plane in the Hastings countryside. Nearby, two nights later, a farmer is discovered shot dead in his armchair. Two Land Army girls working on the farm come under suspicion.

April 1942. Cultures clash as the first Americans arrive to build an airfield near Hastings. Some locals see the "invaders" as a threat. Others find the chance for romance among the young Gis. But when a barmaid turns up strangled. Foyle's investigation strains British-American relations to the breaking point.

December 1942. The death of Grace Phillips, a young worker in a local munitions factory, arouses suspicions. The subsequent murder of Detective Paul Milner's estranged wife, Jane, seems to confirm that Grace's death was no accident. But the evidence points to Milner himself as Jane's murderer.

October 1944. At a psychiatric clinic treating troubled soldiers, the investigation of a doctor's murder turns up no shortage of suspects among the patients and staff. It also complicates Foyle's friendship with Dr. Josef Novak, the Polish refugee who heads the clinic.

Michael Kitchen stars as Detective Chief Inspector Christopher Foyle in this original PBS Masterpiece Theatre mystery series. Set in the beautiful southern English countryside amid the disorder and danger of World War II, Foyle's War takes place far from the glory of the front. His is an ordinary struggle, against everyday evil, in extraordinarily dangerous times.