At half past five the next morning, I hid where I could see the kitchen.

Ottoline switched on the light.

She made my chamomile tea.

And she took out that jar and did the thing my daughter had described, with the smooth, unhurried confidence of a person who has repeated the same motion so many times it has stopped requiring thought.

I will not describe the motion.

It is enough to say that I watched my mother-in-law prepare to poison me with the calm of a woman buttering toast, and that the ground seemed to fall away beneath my feet.