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…