He was holding up his smartphone. It’s approximately fifty-three times more expensive than my own, and on it I could see a shaky video Scott had found on YouTube. He wasn’t the only one—it had 2.5 million hits. The film’s title was “A Real Hero” and it showed a man swimming in the Thames. The camera zoomed in, and the blurred footage showed the man diving into the water and resurfacing a few seconds later with a wet bundle. It was only when he had made it to the bank that it became clear that the bundle was a girl. The man carried the child to Hammersmith Bridge. The picture shook as he strode toward the camera and said, “Were you only filming, or did you think of calling for help?” Four seconds later the car smashed into him. The film broke off. The man was my father.

“Your dad’s a cool dude,” Scott said dryly. “You should tell him that one day.”

The bright burst of joy and energy that had swept through my heart when I caught sight of my father in the film gave way to a dark shadow at Scott’s words. My yearning to tell that living father everything—everything I thought, everything about who I am—turned to despair as I was reminded of his now motionless figure. Motionless and cut off from the world.

Slowly I pulled out the permit that my mother had refused to sign and showed Scott a picture of the back of her Visa card, which I had secretly photographed with my smartphone that morning, just to be on the safe side. I hadn’t actually meant to use it. Until now. Until the film.

“Can you do this one?”

“Easy-peasy,” said Scott, taking my mobile and the piece of paper, and spiriting his fountain pen from its case.

SO AT MIDDAY today I rubbed sand in my eyes and pretended to my French teacher, Madame Lupion, that I’d suffered an allergic reaction. Then I set off for the Wellington with bright red eyes that were still itching and weeping.

No one paid any attention to me in the Underground. No one ever says anything on the tube, and no one looks at anyone either. People act as if they’re alone in the world, even when your face is being pressed into your neighbor’s armpit. The air is seventy-three times more polluted down there than it is aboveground.

Sheila Walker didn’t comment on my eyes either. They really do sting.

Dr. Saul is sticking a sheet of paper to the wall of the waiting room as I enter. It reads: “This is a specialist neurological clinic, not a clubroom, so no slurping your tea and no chatting.” I try to sneak past God without being seen.