The message about the “extra coffee cup” remains unclear and mysterious, adding to the mounting feeling of confusion that Hastings himself clearly feels in relation to the investigation. Poirot, on the other hand, seems to have a perfect grasp of everything that has happened, considering that he has figured out the murderer’s identity. And yet, he
still doesn’t reveal his theories, preferring instead to ponder them on his own while continuing to make enigmatic statements that only heighten Hastings’s—and, in turn, the reader’s—sense of intrigue and suspense.