Christopher was not merely a man who had tried to hurt us.

He was a man who had built, in advance, an explanation — a plausible, sympathetic, airtight explanation — for what was meant to happen to us, and he had rehearsed it, and he intended to be standing in this kitchen looking devastated when the authorities arrived to hear it.

A poisoning you can survive by getting the substance out of your body.

A story like his you can only survive by making it impossible to tell.