Poirot Calendar 2025. More than a century later, the mustachioed belgian detective finally. Hercule poirot appeared in agatha christie’s very first novel, the mysterious affair at styles, in 1920.

Hercule poirot was first introduced by agatha christie in 1920 and since then the popular belgian detective has been the lead character in many of her Hercule poirot appeared in agatha christie’s very first novel, the mysterious affair at styles, in 1920.