‘See you, then.’

‘See you.’

She tried to walk normally, but it didn’t work. Her body wouldn’t let her be calm. She broke into a ragged run, her heart bumping in her chest and a nasty taste in her mouth. ‘Stupid idiot,’ she kept saying. And ‘I’ll kill her. When I see her, I’ll …’ Her legs felt unsteady. She imagined herself getting hold of Joanna by the bony shoulders and shaking her until her head wobbled.

Home. A blue front door and a hedge that hadn’t been cut since her father had left. She stopped, feeling a bit sick, the nauseous sensation she had when she was going to get into trouble for something. She banged the knocker hard because the bell didn’t work any more. Waited. Let her be there, let her be there, let her be there. The door opened and her mother appeared, still in her coat from work. Her eyes took in Rosie and then dropped to the space beside her.

‘Where’s Joanna?’ The words hung in the air between them. Rosie saw her mother’s face tighten. ‘Rosie? Where’s Joanna?’

She heard her own voice saying, ‘She was there. It’s not my fault. I thought she’d gone home on her own.’

She felt her hand grabbed and she and her mother were running back down the road the way she had come, along the street where they lived and up past the sweetshop where children hung around the door, past the man with the pockmarked face and the empty smile, and round the corner out of the shade and into the dazzle. Feet slamming and a stitch in her ribs, over the cracks without pausing.

All the while she could hear, above the banging of her heart and the asthmatic wheezing of her breath, her mother calling, ‘Joanna? Joanna? Where are you, Joanna?’

Deborah Vine pushed a tissue against her mouth as if to stop the words streaming out of her. Outside the back window, the police officer could see a slender dark-haired girl standing in the small garden quite still, her hands by her side and a school bag still hanging off her shoulder. Deborah Vine looked at him. He was waiting for her answer.