When Poirot returned home, he was surprised to find Miss Lemon opening the door for him. She informed him that two visitors were waiting. After a moment of consideration, Poirot decided to meet with Sir Roderick first.

As soon as Sir Roderick saw Poirot, he greeted him warmly. “Monsieur Poirot, my old friend! What a pleasure to see you!” Without delay, he explained the purpose of his visit—several important documents had gone missing, and he was convinced that their contents could compromise national security.

“What exactly do these documents contain?” Poirot asked, his tone measured and curious.

“They are old letters, but now they seem to have taken on significant importance. I suspect that someone tampered with my file cabinet, though I cannot believe it could be anyone in my household.” Sir Roderick replied, also mentioning a young assistant, Sonia, in whom he had unwavering trust.

During their discussion, Poirot picked up on a few key points from Sir Roderick’s account: the delicate dynamics within the household, Sonia’s youthful allure, and the possibility of security lapses at home.

Shortly after, Mr. Goby’s report added more layers to the case. It shed light on Norma’s erratic emotional state, the questionable background of David Baker, and Sonia’s incidental encounter with a foreign military attaché at the Royal Botanic Gardens. All of these elements painted a tangled web of intrigue.

Poirot muttered under his breath, “This is far more intricate than I initially thought… Perhaps, this is not merely a murder case.”