A picture is worth a thousand words. A writer might disagree, but I must admit I devour the photos first if they are on offer. Before embarking on Agatha Christie’s 540-page autobiography, I pored over the pictures of Agatha as a chubby toddler with blonde curls; with Archie, her first husband, and surfboard at Honolulu; with her second husband, Max, excavating in the Middle East. What an adventurous life, where family, friendships, travel and practical work dominated. Writing, it appears, was more of a sideline.

To those of us with literary pretensions, it is absurd that Agatha Christie, the best-selling writer of all time, had trouble thinking of herself as a bona fide author. Maybe writing was too much fun. She would start a book by inventing the characters and hatching the plots in her head, before writing them out in snatches between nursing, photographing archaeological artefacts, running a household, buying and doing up houses, and caring for children, relatives and friends. For many years she had no dedicated workspace and parked her typewriter on any convenient table.

Her motivation to write was often fired by the desire to fund her various projects. In later life, when she had plenty of money, she would make a present of her stories to relatives and friends, who would reap the royalties. During the air raids of World War II, aware of the likelihood she would being killed, she wrote a Poirot book for her daughter Rosalind, and a Miss Marple book for Max. Something to cheer them up after the funeral, she told them.

This autobiography is not so much a literary memoir as the fascinating story of a strong, creative woman whose life spanned the late Victorian era, two world wars and on to the frivolous 1970s. Her memory was prodigious. A large part of the book is devoted to her vivid recollections of childhood, before unfolding through two world wars, when she worked as a hospital dispenser, and two marriages, not to mention the creation of dozens of books. After the war, there was a romantic but gruelling journey to the Middle East with Max, and the start of her work in archaeology. The only time we hear her complain is when she rails at Max for making her ride for fourteen hours across the Peloponnese on a mule!

The tempest of her life abated somewhat around the age of fifty. She welcomed this calmer period, ‘the second blooming that comes when you finish the life of the emotions and of personal relations…It is as if a fresh sap of ideas and thoughts was rising in you.’ It was at this stage she tried her hand at writing plays. ‘The Mousetrap’ opened in 1952 and is still running seventy years on. Not bad for an amateur.

She wrote the final words of her autobiography in 1965, at the age of seventy-five. Although she was a fast writer, this was a side project and took her fifteen years. It is no-nonsense account of a down-to-earth woman, who faced life with hope and pragmatism. She saw it as, ‘not so much a journey back through the past, as a journey forward – starting again at the beginning of it all – going back to the Me who was to embark on that journey forward through time.’