Series 6 of the ITV programme Foyle's War was first aired in 2010, beginning Sunday 11 April; comprising three episodes, it is set in the period from June to August 1945. Series Six was broadcast in the United States on PBS stations on Masterpiece Mystery! as Foyle's War VI on 2, 9 and 16 May 2010, and on Netflix as of April 2014.
Keen to step out of Foyle's shadow and prove himself as a detective, the newly promoted Detective Inspector Milner in Brighton is called to investigate the death of Sam's new employer, a famous artist. Milner is disappointed when Foyle, on the trail of an absconded Russian prisoner of war, arrives at the scene. Foyle's investigation leads him to a supposed safe house in London for members of the Russian Liberation Movement (aka "White Russians"), seeking to avoid repatriation to the USSR. Foyle encounters an international cover up which, if exposed, could bring down the British government.
Foyle investigates a case which is complicated by racial prejudice. Sam and Adam are now running a dilapidated local guest house where Mandy Dean is one of the residents. Disowned by her family, she is a young, vulnerable mother all alone because of the hostility levelled against her and her mixed-race baby. Her ex-boyfriend returns hoping to win her back, but then she is found murdered, and the finger of suspicion points to a black GI at the nearby US military base - the father of her child.
Foyle finally is allowed to resign and leave Hastings police station to his successor, DCS Clarke, his tenure as detective chief superintendent over. After his retirement he makes plans to go to America to "tie up some loose ends" - an oblique reference to his determination to bring American Howard Paige to justice, since he was unable to in the episode "Fifty Ships". But before Foyle leaves, he reads in a newspaper about James Devereaux, the son of a distinguished local family who will be tried for treason for belonging to the British Free Corps, a unit composed of Englishmen fighting for Nazi Germany. If found guilty, Devereaux will be sentenced to death. Foyle decides to look unofficially into the case. He visits Devereaux in his cell and finds a damaged young man intent on self-destruction, unwilling to do or say anything in his defence. With time running out, Foyle desperately searches for any evidence to clear Devereaux's name.