When Ruth Gilmartin’s five-year-old son asks why his granny is so strange, Ruth shrugs it off by saying “Everybody’s strange when you come to think of it.” She has become accustomed to her mother Sally’s idiosyncrasies, such as the sudden decision to move from suburban Banbury to an isolated Oxfordshire village, and the paranoia about people coming to take her away. Just old age, thinks Ruth. But then Sally gives her a document, part autobiography, part confession, entitled The Story of Eva Delectorskaya, and Ruth begins to realise she does not know her mother at all. It turns out that Sally, Russian by birth, had been a spy for the British during the war, witnessing a man shot dead by Nazis in Holland and herself killing a man in New Mexico. Even now, the war long over, she is in fear of her life. In this superb novel, Boyd deftly interweaves the wartime tale of derring-do, of bluff and double bluff, of aliases and murder, with Ruth’s rather more mundane life as an Oxford-based teacher. He has mastered the art of the literary page-turner, mixing thriller techniques such as cliffhanger chapter endings with weightier musings on matters of identity and secrecy. But he has taken risks, too. Another novelist might have based his spy-heroine in France or Germany, at the business end of the war. Boyd instead sends her to Belgium and Canada — places not usually renowned for their dramatic potential, but which, in his hands, become tense locales of espionage and betrayal.

RESTLESS by William Boyd

(Bloomsbury £7.99)

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