‘Manipulating Cassie was easy,’ Singh replied. ‘All it took was some attention and a few gifts, and the girl would do anything for her. Liz wanted to find a way to get revenge on Steve, so she set up the messages. Over the course of a couple of months, she tried different angles with each student, until she found which one of them could be led down the path leading to a relationship. Cassie was roped in to help the others trust Joe. She never knew the idea was to get Steve fired, and most likely arrested. As it was, Steve found the files Liz had saved on his computer and showed them to Liz before she could reveal them – I expect her plan was to “discover” that he’d been grooming a pupil and have him removed. He decided his best course of action was to go to the governors on the Monday, showing them the messages and explaining that he wasn’t responsible, never for one minute expecting that she would follow them up to Normanby Hall and kill him. When Mike called her to tell her about Leon disappearing she was already nearby. She just waited a while before coming back into the park and pretending she’d rushed up there.’

Jane Villiers shook her head. ‘My job now is to try and save the school, for the sake of the students. I don’t want to see any of those five go into a children’s home. This is their home, and I am going to fight for them.’

I didn’t doubt her determination, and I hoped the school would survive the fallout from what had gone on here. One woman’s blind hatred, and desire for revenge, had led to so much damage.

Singh and I walked out together, leaving Forest to take a phone call.

‘You solved your first case as DS, then,’ I said to him.

He gave me a wry smile. ‘Did I? I think you did, when you realised only the killer could have given us Leon’s phone number. Without that, I think we’d still be clutching at straws.’

‘Well, it doesn’t matter how you got there. It’s Leon we really need to thank. If he hadn’t told us about Liz’s plan to kill Cassie, we might not have got here in time. How is she?’

‘She’s recovering,’ Singh replied. ‘The hospital wanted to keep her in for a couple of days. Liz gave her a sedative, just enough to get her in the car and take her back to her house.’

‘Good. I hope she gets some counselling. It can’t have been good for her, having Liz mess with her head like that for months.’

He nodded then took my hand and squeezed it.

‘Paige, I …’ He stopped.

‘What?’