He looks blank. ‘Perhaps we’ll come back to it,’ he says. Then he thrusts The Pocket Guide to Birdwatching into my lap. Green cover. Pencil drawings. ‘We’ll do some ornithology instead.’ He taps the side of his glasses and looks pleased with himself. ‘Have a peek in there. You’ll be amazed at the variety.’

I keep looking for Shane through the slit in the wall. But all I see is grey branches and white steam from the cooling towers.

‘I’ll test you,’ I say, opening the bird-watching book.

‘Go on, then.’ He sits down on the bench and nudges me with a waxed elbow. ‘Do your worst.’

Keeping my thumb over the name, I show him a picture of a bird and read out the description. ‘Active, inquisitive and quarrelsome. Distinctive “tsink-tsink” call.’

Simon wraps his mac tightly around him and shivers as he thinks. ‘It’s a tit,’ he says. ‘I know that much.’

I don’t say anything. He pinches his thin lower lip and closes his eyes. ‘A yellow tit. No, wait. A coal tit.’ He beams. ‘It’s a coal tit.’

‘Wrong.’ I remove my thumb from the name. ‘Great tit.’ Simon shuffles up to me so he can see the book over my shoulder. ‘Close enough,’ he says, his breath damp on my neck.

I close the book and shift along the bench, away from him. After a moment, he goes back to his binoculars, twiddling with knobs and dials. Squinting. Dad used to do the same sort of thing with his record player.

I click my Walkman on.

Just as the chorus of ‘Into the Groove’ is about to start, I see something move in the trees, so I turn the tape off. ‘Let’s borrow those a minute.’

‘I thought you weren’t interested in bird-watching.’

‘I changed my mind.’

Simon flicks his fringe and hands over the binoculars. They’re greasy from his hands. I wipe them on my jacket before bringing them up to my eyes. Peering through them, everything goes tiny. Tiny pool, tiny trees, tiny twigs. I look out at a shrunken world.

‘You’re looking through them the wrong way,’ says Simon. He grabs the binoculars and turns them round. I get a big whiff of his expensive-cheap aftershave.

‘Silly girl,’ he says, holding out the binoculars to me. ‘For all that front, I think you’re a bit silly.’ His smile lengthens. ‘In a rather charming way.’

I let him pinch my knee with a cold hand.

‘Do you think Mum’s silly, too?’

He lets go of my knee, snatches back the binoculars. ‘Even sillier than you,’ he says.

Then I hear something weird. Something like ah-ah-ah.