A hundred years ago, Agatha Christie wrote her first mystery – The Mysterious Affair At Styles – and introduced the world to Hercule Poirot for the very first time.

The author went on to pen another 65 detective novels, 14 short story collections, six romances, and the world’s longest-running play, The Mousetrap.

She has sold over two billion copies of her books worldwide – one billion in the English language and one billion in over 100 different languages. Her books have never been out of print, and, more pertinently, she is the the first crime writer to have 100,000 copies of ten of her titles published by Penguin on the same day in 1948 - A Penguin Million.

So it makes sense that the Royal Mail wanted to celebrate the legendary queen of crime’s career in style.

Agatha Christie’s centenary celebrated with eerie noir postage stamps