Enid Blyton’s books have a reputation for innocence, innocence even to the point of banality, with their handy clues, helpful dogs and lashings of parochial adventure. The truth, however, may be rather less cosy. A new biography of the writer, who is still loved by hundreds of millions of readers all over the world, has discovered a strain of cleverly disguised domestic spite running through her series of children’s books.

Writer Duncan McClaren has researched the real-life connections and resonances in the many books that Blyton wrote during her prolific career for his new study, Looking For Enid: The Mysterious and Inventive Life of Enid Blyton.

While McClaren argues the novelist’s imaginative powers and wit have been vastly under-rated, he has also found evidence one of her silliest characters, the bumbling local policeman of Peterswood in the highly successful Mystery books, was, in fact, a prolonged and sometimes cruel joke at the expense of her first husband, Major Hugh Pollock.

Throughout the series of 15 books, PC Goon is repeatedly humiliated and bested by a gang of five smart children known as The Finder-Outers — Fatty, Larry, Daisy, Pip and Bets, not forgetting Buster the dog. The Mystery books, like her other adventure series, The Famous Five and The Secret Seven, each involve solving a problem or crime and the book jackets were all marked with a magnifying glass and a fingerprint.

Applying his own magnifying glass to the text now, McClaren believes Blyton was laughing at Pollock, the influential older man she married in 1924.

‘Enid loved riddles as a child and had developed a secret code, which I call the box and dot code, which she used to write postcards to her friends,’ he said. ‘Ostensibly, the Mysteries are about the solving of mysteries by the Five Finder-Outers and Dog,’ he argues in his book, ‘To a large degree, the books are really about the ridiculing of Goon.’

The Mystery books were written at a period when she was turning out 20 books a year across all her many series, including The Mallory Towers. For McClaren it is this extraordinary child-like fluency that makesBlyton books still so appealing to children and so charming for adults.