A puff of laughter bursts out of Becca. Joanne’s holy look freezes for a second, but she gets it back.

‘We were in the Needlework room,’ Holly explains. ‘Sewing blankets for orphans in Africa.’

Holly always looks like she’s telling the truth; for a second, Joanne’s eyes pop. Julia says, ‘I had a vision of Saint Fucktardius telling me the orphans needed our help,’ and her face goes lemon-sucking pious again.

‘If you were indoors,’ she says, moving forward, ‘then what’s this?’ She makes a grab at Selena’s hair – ‘Ow!’ from Selena, jumping back – and holds something out in the palm of her hand. It’s a sprig of cypress, rich green, still wrapped in frosty outside air.

‘It’s a miracle!’ Julia says. ‘Praise Saint Fucktardius, patron of indoor gardening.’

Joanne drops the twig and wipes her hand on her nightie. ‘Ew,’ she says, wrinkling her nose. ‘You smell of cigarettes.’

‘Sewing-machine fumes,’ Holly says. ‘Lethal.’

Joanne ignores that. ‘So,’ she says. ‘You guys have a key to the outside door.’

‘No we don’t. The outside door’s alarmed at night,’ Julia says. ‘Genius.’

Which Joanne may not be, but she’s not thick either. ‘Then the door to the school, and you went out a window. Same difference.’

‘So?’ Holly wants to know. ‘If we did, which we didn’t, what do you care?’

Joanne is still being holy – some nun along the way must have told her she looks like some saint – which turns her faintly bug-eyed. ‘That’s dangerous. Something could happen to you out there. You could get attacked.’

That gets another stifled pop of laughter out of Becca. ‘Like you’d care,’ Julia says. They’ve all drawn close, so they can keep to whispers; the forced nearness prickles like they’re about to fight. ‘Skip to the part where you tell us what you want.’

Joanne drops the saint thing. ‘If you get caught this easy,’ she says, ‘you’re obviously too stupid to have the key. You should give it to someone who’s got the brains to use it.’

‘That leaves you out, then,’ says Becca.

Joanne stares at her like she’s a talking dog who’s said something revolting. ‘And you should really go back to being too pathetic to talk,’ she says. ‘At least then people felt sorry for you.’ To Julia and Holly: ‘Can you explain to that uggo why she needs to watch her nasty metal mouth?’

Julia says to Becca, ‘I’ve got this.’

‘Why bother?’ Becca wants to know. ‘Let’s go to bed.’

‘Oh. My. God,’ Joanne says, smacking her forehead. ‘How do you manage not to kill her? Hello, keep up: you need to bother because if I call Matron and she sees you dressed like that, she’s going to know you’ve been outside. Is that what you want?’