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.
October 1940. At the London headquarters of a multinational company, a young secretary plummets to her death. In Hastings, a member of the Home Guard is killed. Foyle and Milner discover how these deaths are linked and how money talks a universal language, even in wartime.
March 1943. While investigating a gambling ring and incidents of sabotage, Foyle becomes distracted by a personal crisis. His troubled goddaughter, Lydia, shows up unexpectedly at his doorstep-along with her young son James, a boy so deeply traumatized by a bomb strike at his school that he refuses to speak.
April 1944. DS Milner's investigation of a transportation fraud sets in motion a series of events that brings Foyle back to the force. As Hastings hosts an ecumenical conference on the morality of continued Allied bombing, Foyle probes the suspicious death of a young cartographer from the Air Ministry office.
August 1945. Foyle probes the mysterious motives of James Devereaux, a former POW and member of the British Free Corps, who refuses to defend himself against treason charges. Meanwhile, Milner investigates the murder of a young woman rooming with the Devereaux family's housekeeper.
When an MI5 intelligence asset fears for his life, Foyle must protect the ex-Nazi from assassination attempts and American authorities. Meanwhile, new MP Adam tries to help a farmer reclaim his land and uncovers information that could threaten his career.