The Deadly Affair (1967)

In 1960s London, Charles Dobbs is a staid MI5 operative investigating Foreign Office official Samuel Fennan, a former Communist who apparently commits suicide. Dobbs becomes suspicious about the cause of Fennan’s death while visiting Fennan’s widow the morning after his death. When a wake-up call is received at Fennan’s home, his widow Elsa says the call was for her. Dobbs discovers this to be a lie, and as a result Dobbs suspects that Elsa, a survivor of a Nazi extermination camp, might have some clues regarding Fennan’s death.

Other government officials want Dobbs to drop the case. However, Dobbs privately links up with retired police inspector Mendel to continue inquiries. They uncover a network of Communist agents. Dobbs also discovers that his wife Ann is leaving him to go to Switzerland to join a former World War II colleague, Dieter Frey, who may be using Ann to gain knowledge of Dobbs’ investigation.