I put three of the eggs back in the dish, but kept one of the larger ones out. I turned it in my hand so that my palm cupped the fat base of the egg. “What you can’t see, Eliza, is a tiny hole here at the top of the egg. It is covered, now, with a matching wax, but if you’d been here yesterday, you would have seen a tiny black dot where I inserted the poison with a needle.”

“It did not break!” she exclaimed, as though I had demonstrated a magick trick. “And I cannot even see the wax.”

“Precisely. And yet, there is poison inside—enough to kill someone.”

Eliza nodded, gazing at the egg. “What kind of poison is it?”

“Nux vomica, rat poison. An egg is the ideal place for the crushed seed, as the yolk—viscous and cool—preserves it, no different than if there were a baby chicken inside.” I returned the egg to the dish with the others. “You’ll be using the eggs soon?”

“Tomorrow morning,” Eliza said. “When he is home, my mistress and her husband eat together.” She paused, as though imagining the breakfast table laid out before her. “I will give my mistress the two smaller eggs.”

“And how will you tell them apart, after you have dumped them into the pan?”

This stumped her, but only briefly. “I will cook the smaller eggs first, set them on the plate meant for my mistress and then cook the larger eggs.”

“Very good,” I said. “It will not take long. Within seconds, he may complain of a burning sensation in his mouth. Be sure to serve the eggs as hot as you can so he does not know any better—perhaps underneath a gravy or pepper sauce. He will think he’s only burned his tongue with the heat. Soon after, he will feel nauseous, and he will most certainly want to lie down.” I leaned forward, making sure Eliza clearly understood what I was to say next. “I suggest you do not permit yourself to see him after this.”

“Because he will be dead, you mean,” she said, expressionless.

“Not immediately,” I explained. “In the hours after ingesting nux vomica, most victims suffer a rigid spine. They may arch backward, like their body has been strung into a bow. I have never seen it myself, but I have been told it is horrifying. Indeed, the cause of a lifetime of nightmares.” I leaned back into my chair, softening my gaze. “When he dies, of course, this rigidity will release. He will look much more peaceful then.”

“And later, if someone asks to inspect the kitchen or the pans?”

“They will find nothing,” I assured her.

“Because of the magick?”