She paused, hesitating.

“Arsenical poisoning?” said Poirot helpfully.

She nodded.

“And then, too, he, the patient, I mean, said something queer. ‘They’ll do for me, the four of them. They’ll do for me yet.’ ”

“Eh?” said Poirot quickly.

“Those were his very words, M. Poirot. He was in great pain at the time, of course, and hardly knew what he was saying.”

“ ‘They’ll do for me, the four of them,’ ” repeated Poirot thoughtfully. “What did he mean by ‘the four of them,’ do you think?”