‘One minute.’ He ducks round the partition wall that separates Kira’s exhibition from the one beside it. A couple of seconds later he reappears.

‘She’s gone out for coffee.’

‘Yeah.’ A young woman with pink hair twisted into a messy topknot pokes her head around the partition. ‘She said she was meeting someone. Didn’t say who.’

‘Do you know which café?’

She shakes her head. ‘Sorry, no. Somewhere on Queen’s Road probably. I don’t imagine she’ll have gone far. She’s got to get this finished before we open on Monday.’

She gestures towards the row of canvases propped up against the base of the wall. I half-glance at them, then do a double-take.

‘What’s this?’ I crouch down by the canvas at the far end of the row.

‘Careful!’ Mason says as I reach for it. ‘You shouldn’t be touching—’

‘Billy.’ I point at the black inky image in the centre of the canvas. The word is almost lost in the abstract spikiness of the design but I know what it says. DStroy. ‘Billy drew this.’

‘What?’ He tilts his head to one side. ‘I’m not sure I—’

‘It’s one of my son’s graffiti designs. I’m sure it is. I’ve seen it before, in the sketchpad he kept by his bed. Did Kira say whose tattoo it is?’ I look from Mason to Pink Hair who is standing beside me, arms spread wide as though readying herself to protect Kira’s exhibition. They both shake their heads.

I scoot across to the other end of the row where a pile of cardboard descriptions is stacked neatly and sort through them, flicking them to the floor as I read.

Me and my best mate thought it would be fun to …

It was my stag night and I was drunk …

I really liked My Little Pony as a kid and …

‘Whoa!’ Mason grabs holds of my wrist as Pink Hair dips down to gather up the discarded cards. ‘I don’t know what you think you’re doing but you’re damaging private property. Kira’s worked really hard to—’

‘It’s not here.’ I snatch my wrist away from him. ‘The card that describes that tattoo. It’s not here. Where is it?’

I spot a black art folder propped up against the partition but Pink Hair gets there first. She whips it up by the handle and holds it away from me.

‘Can we get security?’ She looks at Mason who nods.

‘You don’t understand,’ I say. ‘I know Kira. She’s my son’s girlfriend. And this tattoo. This DStroy symbol. My son drew that. My son Billy. He’s been missing for over six months.’

Pink Hair takes a step back, into the crowd of students who have congregated around us. They are all staring at me as though I’m one of the exhibits.