The following is a brief, official synopsis. For a detailed account of the episode, click here.Click the pictures to enlarge.
It's August 1942. A mysterious bomb is dropped in deserted, barren land and smoke envelopes a cage of sheep. Later, a dead sheep falls out of a van into a country lane.
GI Joe Farnetti shocks Sam by proposing to her, while Milner is also surprised by a plea for help from his one-time love Edith Ashford. Edith's brother Martin, a Quaker and conscientious objector, has been accused of murdering war hero Tom Jenkins.
Jenkins served with the Royal Navy and saved his men when a convoy of ships was attacked by Germans. He was honoured by the King. The case is outside Foyle's jurisdiction but he agrees to visit DCS Fielding, a former army colleague.
Vet Ted Cartwright, whose son Leonard was also on the besieged ship, is called out to Foxhall Farm, where Brian Jones' cows have gone down with a mysterious illness.
Fielding reluctantly lets Foyle look into his murder case. Tom Jenkins and Martin Ashford argued violently and arranged to meet on the beach to settle their differences. Jenkins was killed and his blood was found on Ashford's clothing,
with a knife in woodland nearby. Ashford claims he is innocent but won't talk to the police. The evidence is mounting against him but Foyle realises he's not being told everything.
Meanwhile, the sick cows disappear from Foxhall Farm - where Ashford works. Jones seems more upset about their theft than either Ashford's arrest or the death of Jenkins - his son in law. Fielding gives Foyle the murder weapon - a trocar, used by vets. It belongs to Ted Cartwright.
Sam and Jenkins' widow Elsie are both ill with flu. The police receive an anonymous letter claiming the killer was a
tall man with white hair. Edith eventually admits that her brother was having an affair with Elsie, and Jenkins was a violent man. But Elsie died that morning. Her final delirious words were about a dead sheep.
Ashford tells Foyle he feared Elsie would be charged with her husband's death unless he took the blame. Meanwhile Sam goes to hospital, her body covered in black sores. Police stop another Quaker, Henry Styles, from leaving Hastings and he tells them the disease is anthrax, caused by a biological warfare experiment that went wrong.
As he's on the verge of cracking the murder case, Foyle must venture into the most secretive aspects of the war to find the answers that could save Sam.
Thanks to ITV for the publicity stills and to Shelagh for the press-pack.