I get into the car, turn over the engine.

“Signal your intent,” Dad says, in that automatic way he does when he recites the rules of the road. He remembers all of them. There must be some cordoned-off areas in your brain where dementia cannot reach.

I indicate as instructed, then ring the yoga retreat before driving off.

But Iris is not there. She never arrived.

In fact, according to the receptionist who speaks in the calm tones of someone who practices yoga every day, there is no record of a booking for an Iris Armstrong.

Iris told me not to ring her mobile this week. It would be turned off.

I ring her mobile. It’s turned off.

I drive to Iris’s cottage in Feltrim. The curtains are drawn across every window. It looks just the way it should: like the house of a woman who has gone away. I pull into the driveway that used to accommodate her ancient Jaguar. Her sight came back almost immediately after the accident, and the only damage was to the lamppost that Iris crashed into, but her consultant couldn’t guarantee that it wouldn’t happen again. Iris says she doesn’t miss the car, but she asked me if I would hand over the keys to the man who bought it off her. She said she had a meeting she couldn’t get out of.

“It’s just a car,” she said, “and the local taxi driver looks like Daniel Craig. And he doesn’t talk during sex, and knows every rat run in the city.”

“I’ll just be a minute, Dad,” I tell him, opening my car door.

“Take your time, love,” he says. He never used to call me love.

The grass in the front garden has benefited from a recent mow. I stand at the front door, ring the bell. Nobody answers. I cast about the garden. It’s May. The cherry blossom tree, whose branches last week were swollen with buds, is now a riot of pale pink flowers. The delicacy of their beauty is disarming, but also sad, how soon the petals will be discarded, strewn across the grass in a week or so, like wet and muddy confetti in a church courtyard long after the bride and groom have left.

I rap on the door even though I’m almost positive Iris isn’t inside.

Where is she?

I ring the Alzheimer’s Society, ask to be put through to Iris’s office, but the receptionist tells me what I already know. That Iris is away on a week’s holiday.

“Is that you, Terry?” she asks and there is confusion in her voice; she is wondering why I don’t already know this.

“Eh, yes, Rita, sorry, don’t mind me, I forgot.”

Suddenly I am flooded with the notion that Iris is inside the house. She has fallen. That must be it. She has fallen and is unconscious at the foot of the stairs. She might have been there for ages. Days maybe. This worry is a galvanizing one. Not all worries fall into this category. Some render me speechless. Or stationary. The wooden door at the entrance to the side passage is locked, so I haul the wheelie bin over, grip the sides of it, and hoist myself onto the lid. People think height is an advantage, but I have never found mine—five feet ten inches, or 1.778 meters, I should say—to be so. Imperial or metric, the fact is I am too tall to be kneeling on the lid of a wheelie bin. I am a myriad of arms and elbows and knees. It’s difficult to know where to put everything.