“A mistake,” said the detective. “It happens all the time. Either they use way too much or way too little.”
“Not all the time, Lieutenant. And from what’s happened so far, I don’t see this character ― whoever he is ― as the impulsive, emotional type of killer. If this is all tied up, it has a pretty careful and coldblooded brain behind it. The kind of criminal brain that doesn’t make simple mistakes like underdosing. ‘Not sufficient to cause death’... that was deliberate.”
“But why?” howled young Macgowan.
“ ‘Slow dying,’ Mac!” said Laurel triumphantly. “Remember?”
“Yes, it connects with the note to Hill,” said Ellery in a glum tone. “Nonlethal dose. Enough to make Priam very sick, but not fatally. ‘Slow and sure... For each pace forward a warning.’ The poisoning attack is a warning to Roger Priam to follow up whatever was in the box he received the morning Hill got the dead dog. Priam’s warning number one ― unknown. Warning number two ― poisoned tuna. Lovely problem.”
“I don’t admire your taste in problems,” said Crowe Macgowan. “What’s it mean? All this ― this stuff?”
“It means, Mac, that I’m forced to accept your assignment,” replied Ellery. “And yours, Laurel, and yours, Delia. I shouldn’t take the time, but what else can I do?”
Delia Priam came to him and took his hands and looked into his eyes and said, with simplicity, “Thank you, Ellery. It’s such a... relief knowing it’s going to be handled... by you.”
She squeezed, ever so little. It was all impersonally friendly on her part; he felt that. It had to be, with her own son present. But he wished he could control his sweat glands.
Keats lipped his unlit cigaret.