Because I was told to keep it a secret, she insisted, her eyes shining. I didn’t want my friend to stop being nice to me. But then Mike was attacked. She looked down at the table. I’m worried it was my fault. I thought he might have been my friend, because he’s always nice to me. Leon asked me about my new shoes and I told him I thought Mike had bought them for me. He thought it was really funny and told everyone I was making up stories about Mike buying me presents.

The detectives looked at each other. ‘We don’t know if these things are connected, Cassie,’ Forest said, ‘but we need to look into them. Please will you let us have your phone, so we can see the messages you got from your friend?’

She shook her head. I told you, I lost it.

‘Have you had any messages from your friend in the last week?’ Forest asked.

No. They only text my new phone now, and I haven’t had it since the weekend we went on the trip.

‘What about the presents? Could you write us a list of what they gave you? And did you keep any of the notes that came with them?’

For a moment I thought Cassie was going to shake her head again, but then she sagged a little. I kept some, yes.

‘Where are they?’

In a box in my room.

‘Okay Cassie, when Sasha takes you back to school I’m going to come with you and collect those notes.’

Why? I want to keep them.

‘They might help us to find out who your friend is.’

Can I have them back afterwards? There was an earnest look in her eyes, and I wondered how lonely she must have been for this ‘friend’ to get her so completely under their spell.

Cassie and Sasha left, and Singh was about to follow when Forest got a phone call. She held up a hand telling him to wait, and I hovered next to him.

‘What?’ she exploded. ‘Are you absolutely certain?’ There was a pause as the person on the other end spoke. ‘Right,’ Forest continued. ‘I’ll send a car and a couple of PCs to collect him. Don’t let him leave. I don’t care what you have to do, that man is about to be placed under arrest and if he discharges himself before my officers get there I will hold you personally responsible!’

She hung up with a snarl and looked over at Singh. ‘I can’t bloody believe it,’ she began, then spotted me over Singh’s shoulder.

‘You, out,’ she barked at me. ‘You can’t be here for this.’