Lance was the one holding the knife, and his other hand had seized Ben’s shoulder. In front of him, Callum was taking something from his pocket. It looked like a rolled-up piece of fabric, and slowly he began to unwind it.

‘You still don’t understand, do you?’ Callum said. ‘This is what we want. It’s what we’ve wanted from the start.’

Melissa had edged into Ben’s eyeline, but when he turned pleadingly towards her, she looked away.

Callum, meanwhile, took a step closer, and Ben finally recognised what he was holding. It was a stole – a priest’s scarf – like one of the ones Father Steiner sometimes wore when he was conducting a service. Not just like Father Steiner’s, in fact. It was Father Steiner’s, and that was when Ben finally understood.

‘No,’ he said. ‘No! Please, don’t do this!’ He shook his head, forgetting about the knife, and the tip of the blade once again pierced his skin. He hardly felt it, but he sensed Lance flinch slightly, as though he were the one who’d been hurt.

Callum continued moving forward. The white and gold fabric of the stole was stretched tightly between his hands.

‘It’s perfect,’ he said. ‘Don’t you see? Last time it was Melissa’s word against a teacher’s. Which might have been enough if Father Steiner hadn’t interfered. And if Melissa had held her nerve.’

He didn’t so much as glance Melissa’s way, but her eyes dropped towards the ground.

‘This time, the evidence will be laid out for everyone to see,’ Callum went on. ‘It will be as simple as reading a picture book. Father Steiner lured you in, giving you gifts and pretending to be your friend. He tricked you into having a relationship with him, and when you decided you wanted to end it, and threatened to expose him for what he was, he lost his temper. Maybe he didn’t mean to hurt you. Maybe it was the only way he could be certain you’d stay quiet.’

Callum wrapped the ends of the stole around his fingers.

‘And the best part is,’ he said, ‘nobody will have the slightest clue that any of us were involved. Nobody really thinks we’re your friends. Even if somebody saw us come out here into the woods with you, we’ll claim you went off on your own, and chances are they won’t find your body for days anyway. Not until they think to drain the lake.’

Ben’s eyes flicked involuntarily to the steel-grey water, which continued to boil under the strengthening rain. ‘But why?’ he pleaded. ‘Why are you doing this?’