When the diffident and ineffectual Derek Mann loses his teaching job in a girls' grammar school in England and drifts from one temporary post to another, one of his precocious pupils gives him her grandfather's wartime diary with a mission to return to Apartheid South Africa and find the opal mine she believes to be her rightful inheritance. Intrigue and violence bedevil the quest that ends in a desert under the Southern Cross. The wry, often laconic style gives full reign to the characters' latent sexuality. While the novel takes the form of a thriller, it is also a love story. The plot pivots round the war-diary of a man whose bomber was shot down in action in Egypt in 1941. The man had invested money in partnership with his wartime friend in an opal mine in a place designated by the letters 'C.P.' in 'S.A.'. His granddaughter's search for the mine affects her own as well as her former teacher's destiny.