I went to the Harrogate crime writing festival last year and saw an interview with author Charlotte Philby about her new book Edith and Kim – the fictionalised story of her grandfather Kim Philby’s friendship with Edith Tudor-Hart, who introduced Kim Philby to his Soviet handler Arnold Deutsch.

Peppered with real letters sent from her grandfather and extracts from intelligence files, this novel tells Edith’s story, one of passionate ideology that surpasses all things, except for her troubled son Tommy. Edith lives a life always watchful, always waiting for a knock at the door, and looking for a long-term love she never finds in a succession of passionate affairs.

She lives through the Blitz in London, meets Anna Freud, daughter of Sigmund (fifty years into the profession of psychoanalysis), in a failed effort to help her son, makes her own living through photography, her camera the key to her spying, is watched by the British authorities and has around her a group of fascinating communist friends. Throughout it all is her friendship with Kim, told through a series of letters to her from him, Kim now settled in the Soviet Union and reminiscing about his earlier life.

This is such an interesting previously untold story of the woman at the heart of the Cambridge spy ring and a must-read for anyone interested in this fascinating period of pre and post war history.