James Penfield, Jonathan Pryce, is an ambitious London-based BBC radio reporter who rises from humble origins to an Oxford-educated professional. He is commissioned to write a book on the Suez Crisis, claiming not to be a socialist, even as the Falklands War dominates the British media.
James Penfield becomes attracted to Susan Barrington, Charlie Dore, a snobbish upper-class TV journalist, and is introduced to her by his Oxford friend, Jeremy Hancock, Tim Curry, a fellow TV journalist. Despite his persistence, he cannot get beyond a late-night kiss from her; so Jeremy suggests he contact her mother, Ann Barrington, Rosemary Harris, a prominent left-wing historian who is married to advertising film director Matthew Fox, Frank Finlay.
With Ann, James presents himself as a socialist, spending more time with her than with Susan; they share long conversations and walks on the Norfolk Broads. Meanwhile, James's mother is dying, and he had earlier told Susan that his parents were dead to disguise his origins; he is forced to identify his mother only as a relative when his father contacts him while he is with Ann.
Back in London, he needs help from members of a women's peace camp after a puncture; at first mistaken for another BBC man, he feigns sympathy toward the group protesting outside a Norfolk airbase. On another visit to Norfolk with an uninterested Susan, James walks alone with Ann, who kisses him and later has sex with him.
James returns to his work in London, and over a ploughman's lunch and beer with Matthew Fox, Fox consents to James making love to his wife, since the couple had slept in separate beds for the last three years. James refuses to take calls from Ann when she tries to contact him at the BBC. He’s asked by another Oxford friend, an up-and-coming poet, to end the relationship, while he sits idly by reading advertisements in Exchange and Mart.
James, Jeremy, and Susan travel to Brighton together to cover the 1982 Conservative Party Conference. At the start of the conference, James begins to suspect that the other two are romantically involved, and asks Jeremy if he is up to something. Later, during the conference, he attempts to talk to Susan but she brushes him off; he then sees her and Jeremy caressing each other, having returned from a hotel room.
The conference finishes with Thatcher's closing address as she rouses popular support following the Falklands War, and afterwards James confronts Jeremy in the Brighton Centre, rebuking him for having betrayed him; Jeremy tells him that he has known Susan for fifteen years and that they are “old allies.”
James has a conversation with his publisher about the success of his book. He then attends his mother's funeral, standing grim-faced and aloof at his father's side, as he impatiently checks his watch.
