‘What brings you here?’ said Marcus.

‘We have early forensics,’ said Agatha. ‘Bree passed away three days ago, the cause of death a broken neck from hanging. It would’ve been quick and painless.’

Isabel sat down. ‘Days ago?’

‘How could she have been there that long?’ said Marcus.

‘We’re not sure yet,’ said Agatha. ‘What we do know is that the same rope that killed her is the one she was hanging from. How everyone missed her hanging there for days . . .’

‘It’s impossible,’ said Marcus. ‘I know people were there. I walked that path myself – I walked the entire trail from the school to the Trapper’s Hut. I even saw people at the Hanging Tree, bringing flowers. Bree was not there three days ago.’

‘So someone killed her?’ said Isabel, hands to her mouth.

‘We don’t know that,’ said Agatha. ‘Her stomach was full of fruit, chocolate, potato chips, dried meats. Nothing like what was found in Georgia’s stomach, nor did they eat it during the camp, as far as we know. If Bree did kill herself, she found somewhere to stay between disappearing from the path and the moment she died . . . and that’s why we wanted to speak to you. Do you know anywhere Bree might have gone that has horse chestnut trees?’

‘What are those?’ said Isabel, turning to her husband.

‘I didn’t think they were edible,’ said Marcus.

‘No,’ said Agatha. ‘We found traces of them on her shoes.’ She pulled a photo out of her folio and laid it flat. It showed a horse chestnut. Con knew he’d seen some, and recently, but where?

‘We called them conkers when we were boys,’ said Marcus, picking up the page. ‘You play a game where you knock each other’s until they break, but we always just pegged them at each other across the footy ground.’ He looked up, right as Con remembered.

‘At the school,’ said Con.

Marcus nodded. ‘There’s a big row of them, right along the main driveway.’

‘Are they building anywhere at the school?’ said Con, remembering the concrete dust in Bree’s clothes.

‘Yes . . . half of the Home Economics block is being renovated,’ said Marcus. ‘Bree loved Home Ec.’

‘Thank you, Mr Wilkins,’ said Agatha.

‘No one will be there today,’ said Isabel, ‘the students are staying home. Most of them would’ve been there . . . last night . . .’ She took a deep, shuddering breath. ‘Did Madison really plan all of this?’ she finished in a whisper. ‘Bree hated Madison.’

‘I think it might be best to show you some footage we’ve recently recovered,’ said Agatha. ‘It’s confronting, I’ll warn you, but it may shed some light on your daughter’s headspace.’

‘Just ask, why don’t you?’ said Isabel.

‘Ask what, Mrs Wilkins?’ said the commander.