The British crime-writing legend Agatha Christie wrote a whopping 66 detective novels in her lifetime – and won a legion of fans with classics such as Murder on the Orient Express and The Murder of Roger Ackroyd.

As the biggest name in crime writing since Arthur Conan Doyle, Christie unsurprisingly found herself adored by legions of fans across the globe. She is also widely considered one of the best writers in British history.

In 1972, one fan from Japan wrote to Christie listing their favourite novels from her catalogue.

Agatha Christie wrote a letter in response, listing her own 10 favourite books. But she left one of her classics out of the ranking.

Writing to her fan, the author said: “My own ten would certainly vary from time to time because every now and then I re-read an early book for some particular reason, to answer a question that has been asked me perhaps, and then I alter my opinion – sometimes thinking it is much better than I thought it was – or not so good as I had thought.”

She went on to list her 10 favourite books – including Murder on the Orient Express, Crooked House and A Murder is Announced.

But, surprisingly, she left one fan favourite out of the running: Death on the Nile.

Her 1937 classic features her iconic Belgian detective Hercule Poirot as he hunts for a mystery murderer aboard a river steamer on the Nile.

The novel has a 4-star average rating on Goodreads with over 270,000 user ratings – making it one of the most-read books on the platform.

The iconic mystery was also recently turned into a film starring Kenneth Branagh as Poirot.