The three of us stared at the dog, our mouths hanging open.

I was the first to recover.

“You want to use one of us … as a guinea pig? You want one of us … to volunteer to take poison? You can’t be serious!”

“Of course not, my dear Catson,” the dog said. And there was that wide grin again. “Well, maybe just a bit.”

“Do you think those might be what killed er, John Smith?” I said. “If so, I can simply sniff them for you. If they smell of almonds, there’s our answer.”

“Ah, but what if they smell of almonds and yet they’re not laced with cyanide?” he said. “What if they’re simply some harmless almond-scented pills? No, I’m afraid we need more conclusive evidence here than your nose can provide.”

Before I could respond, the dog rose from his seat at the table, pocketing the pillbox in the palm of his paw.

“Where are you going with those pills?” I said as he began to move away from the table.

“Well,” he said, as though the answer must be obvious, “if I can’t get any volunteers here, I shall have to look elsewhere, won’t I?”

“Where are you going?” I called, more desperately. But he was soon through the doorway and out of view, his voice traveling back to us:

“I need to see a dog about a man.”