Summary: American troops arrive in Britain and the Corps of Engineers building an airstrip on a Hastings farm is met with resentment.

Summary: August 1942. Foyle investigates the a mysterious disease affecting local farm animals and looks into the arrest of a pacifist accused of stabbing a war hero.

Summary: Foyle busts a restaurateur for offering illegal Christmas foods which are then confiscated as evidence. He then begins to investigate the death of Grace Phillips, a munitions worker who accidentally killed herself on the job. Tensions at the funeral begin to cast suspicion on her scheming lover, Harry Osborne, just as suspicions fall on Milner over the sudden and "convenient" murder of his wife after a public row over their divorce in a hotel. Meanwhile, another worker, Phyllis Law, tries to blackmail Eddie Baker, the factory foreman, over a dubious collection for Phillips's ageing mother (since she discovered she was in fact an orphan). It is also revealed that Phillips and Mrs Milner knew each other as hairdressers before the war. Constable Peters admits his duplicity in manipulating evidence to get back at Milner over his earlier reprimand of him. In the end Foyle confronts Osborne in the bank cellar, where it is revealed that Osborne had Phillips steal explosives in order to break into the safe at the bank next to the hairdressers, later using rat-poison to silence her, and killed Mrs Milner to steal back a condemning letter written by Phillips.

Summary: Two local youths, brothers Terry and Frank Morgan, break into a local wealthy mansion but are co-opted into an apparent pacifist sabotage ring led by Spaniard Jose de Perez. Meanwhile, Milner is asked to infiltrate and investigate a gambling ring as Foyle is confronted by the new straight-laced Assistant Commissioner Henry Parkins. In addition, Foyle's goddaughter Lydia Nicholson and her traumatised young son James come from London to stay unexpectedly. As he struggles to readjust to sharing his house, things become difficult as Lydia suddenly goes missing, and is later found alive after a suicide attempt. Meanwhile, a local reports hearing a shot fired near a secret admiralty research centre. Upon investigation, the body of Michael Richards, a local teacher with gambling debts, is found half-buried in the woods near where his wife Evelyn works. The leader of the facility, an old professor acquaintance of Foyle, is initially unable to provide any assistance, but seems surprised when Foyle asserts that Richards was lured there by his wife and killed by her Danish lover Hans Lindemann. However, when Foyle is again prevented from bringing the culprits to justice due to national concerns, he immediately tenders his resignation in protest.