I swing past to check on Sam, and see him sitting on the shop floor with rows of games fanned in front of him. I snap a photo of him through the window and he doesn’t even look up. If I turn it black and white, if I tweak it to make it look pixellated and gritty, it would look exactly like a surveillance photo.

At the camera store I look at digital SLRs I’ll never be able to afford, not even if I take off a hypothetical $500 won hypothetically in the non-hypothetical art prize and then add all the pocket money I can save this year. Mum’s old camera is a dinosaur compared to these muscly black models. I wish I’d thought to sign out one of the school’s fancy cameras for the weekend, so I could have practised with it. Brooke and Audrey take all their photos on film and use the darkroom to develop and print them, but we didn’t have a darkroom at Morrison, and I don’t have time to learn how to do it well enough for my project.

When I’ve looked at every camera in the shop, I retrace my steps to the games store to collect Sam.

The corner where he was sitting is empty now. I scan the store, looking in front of each shelf and bargain bin. Everywhere I look there are rows of browsing backs. Sam’s not at the info counter, or hiding behind a cardboard cut-out display.

I go to the front counter.

‘Have you seen a little kid? He’s ten, about this tall?’ My voice sounds normal even though my insides don’t. The sales assistant stops pricing games with a sticker gun.

‘Oh, hey,’ he says, as if he knows me. ‘Who are you looking for?’

‘My brother. He’s wearing a purple jumper and jeans, maybe?’

‘Sorry, no. Nick, you haven’t seen a kid on the loose have you?’

His work colleague shakes his head.

The assistant puts down his gun. ‘Do you want some help looking for him?’

‘No, no thanks.’

I exit the store and look both ways up the aisle, a frantic feeling already coming on. I look at waist level among the crowds of shoppers. No Sam.

I turn to ice. My fingers, toes, all the way to the ends of my hair, and especially my heart.

I walk to the end of one aisle, look up and down the next row of shops, then go back to the other end and robotically repeat the action.

Sam is gone.

The next obvious place to check is the large entrance to the shopping centre. To the right is the food court where we ate dinner, to the left the gates to the subway.

I consider the sliding doors to the underground platforms. I picture a man holding Sam’s hand and leading him down the escalators, onto a train, and away. Forever. In my chest is a cold fist.

‘Chlo? Chlo?’

I turn so quickly I get vertigo.