The detectives wanted to interview Jess Farriday again, to see if she had had any suspicion about what Steve was doing. She was visibly trembling when she came into the meeting room, though whether it was from anger following the run-in in the hall with Cassie, or distress at the revelation about Steve, I couldn’t tell. Singh had decided to continue conducting any interviews at the school in order to minimise the disruption for staff and students. That, and it was about fifty minutes from the school to the police station in Scunthorpe, so it prevented any wasted time asking staff to travel. Lincoln didn’t come under the jurisdiction of Humberside police, being in Lincolnshire rather than North Lincolnshire, but because the crime had taken place at Normanby Hall it was still under Humberside.

It felt strange to be sitting here opposite Jess, knowing she had dated both my current and ex-boyfriend, and was possibly seeing Mike again. We were so different, in looks and temperament, yet we’d both been attracted to the same men. In her teenage years she’d been a bully; was she still the same? She was slimmer than me, and prettier, and I found myself wondering if Max would prefer her to me if he had the opportunity to date her again. Shaking the thought off, I concentrated on the conversation.

There must be some mistake with your evidence against Steve, Jess told the detectives as soon as she sat down. You’re wasting your time with this when you should be trying to find Leon.

‘What sort of mistake?’ Singh asked gently.

There’s no way Steve could have been involved in anything like that. Maybe he was trying to show the kids the dangers of talking to strangers online? she suggested.

‘The nature of the messages that passed between him and Leon go far beyond what could be considered reasonable in that situation.’

There was desperation in Jess’s eyes, and I felt a pang of sympathy for her. It must be awful to discover the man you had been dating was hiding such a terrible secret.

I still can’t believe it, she repeated, shaking her head. He would never do anything like that. I was dating him, I’d know if he was the sort of man who would do something like that!

Singh leant forward slightly. ‘Miss Farriday, I completely understand your position. Nobody ever wants to know that someone they care about is capable of committing a crime, but unfortunately it does happen. Men like that are skilled at hiding their actions, because they know how other people would view them.’

Could there have been a mix-up with accounts? she persisted. Maybe the techs made a mistake.

‘One of our forensic IT officers is examining the school system as we speak,’ he told her. ‘If anything got mixed up, or if things were transferred from one account to another, we’ll know about it.’