Farthing is set in a world where the British agreed to a peace with Hitler in 1941, eight years ago. This book starts out like a classic British murder mystery: a prominent right-wing politician is murdered at the Farthing country estate and Scotland Yard are called in. The story is told from two viewpoints, that of the secretly homosexual Inspector Carmichael and that of the daughter of the house, Lucy Kahn, who married a Jew. The dead man has a yellow star pinned to his chest, making David Kahn a likely suspect.
The murder precipitates Britain’s further descent into a police state, and both Lucy and Carmichael lose their illusions as it happens.