During the Malayan guerrilla war in the 1950s, Ah Lin is a Chinese amah, a children's nurse, to a British family, the Creasleys. Unbeknown to the family Ah Lin is also a secret courier working for the communist guerrillas and her brother is a guerrilla soldier in the jungle. And unbeknown to Ah Lin, Mrs Creasley works in Special Branch in the Malay police. The Creasley family, in particular the daughter Mary, suffer from the constant threat of guerrilla terrorism against the British. And for Ah Lin's family there is deep anxiety and tension as the war progresses. They know that if Ah Lin's double life is exposed she will be charged with treason and hanged. In the end these fears materialise in an unexpected way.

Sir Crispin Whipple is the newly appointed UK Ambassador to the Western Allied Military Pact Organisation (WAMPO) in the early seventies, and in his first year he experiences the embarrassment of two espionage incidents traced to the UK Delegation. MI5 are called in to investigate and, having several other unsolved espionage incidents on their books, they are anxious to nail a British spy ring. Sir Crispin is also unprepared for the mutual distrust and bickering that goes on between the WAMPO member states, who pursue their own political agendas. The story is set against the background of the Cold War, the US President's re-election, the Icelandic Fisheries war, WAMP military facilities on Malta, Russian spies and secret Exercises. WAMPO's response to world events contrasts with the more serious problem of their headquarters building which is falling down owing to wrongly mixed cement.