Pubblicato in Italia con il titolo Poirot e i quattro. Poirot e il suo amico Hastings si trovano ad affrontare una cospirazione a livello internazionale. Riusciranno a fermarli?

Hercule Poirot is getting ready to travel to South America for a very important job when he receives two surprises: first, his dear friend Hastings turns up after two years away and then a stranger passes out right in his room. Who is he? And what’s the significance of number four? As Poirot and Hastings investigate, they uncover an international conspiracy that involves four very powerful people who intend to subvert the existing social order. But how can they stop them?

Written in 1927, this is a gripping spy story full of twists and turns, fake deaths and fake identities, and near-death experiences. It’s brilliant in its complexity and development and I couldn’t recommend it enough!