I stare at her, frowning. It’s easy to imagine Andrew Buckley threatening them, but if Hollie and Dylan were in love, this was hardly enough to stop them ‘And you’re sure Dylan wrote that just before he died?’

Niamh nods. ‘It was the day before. He left the letter in his room. I went in there before the police got there and took it. He wouldn’t have wanted anyone else to read it. Just Hollie. But if she had …’ She tails off.

‘You thought she’d be angry with your father, so you didn’t give it to her – until recently,’ I say quietly, remembering how the tyres on Andrew Buckley’s car were slashed. It’s why you became friends, isn’t it?’ My heart twists as I look at her. ‘You were each other’s links to Dylan. No-one else could understand.’ I wonder how Hollie could have tolerated seeing Andrew Buckley, knowing what he’d said to Dylan – unless she’d been waiting while she planned a way of getting back at him. Except she ran out of time.

‘What happened that day Hollie took you to Phil Mason’s house?’

‘We went in the back way. She checked no-one was in, then she showed me this building that wasn’t part of the house. There was a window …’

‘What did you see?’

‘Photos.’ Niamh’s voice is soft. ‘Of girls.’

Glancing at Elise, there’s a look of horror on her face.

‘Niamh? We know about the photos.’ Trying to reassure her, I wonder how much she could have made out through the window. ‘And we’re holding Phil Mason.’

‘And my father?’ The words, reed-like, chill me. Did Niamh know about Andrew’s involvement?

‘What did Hollie know about your father?’

‘She said he knew Phil Mason – very well.’

‘Is there anything else we should know, Niamh?’ But as she shakes her head, I know that even if there’s more, she’s told me all she’s prepared to at this stage.

I turn to Elise again. ‘I have to get back to the office.’

Getting up, she walks with me to the door. ‘There’s something else.’ Her voice is low, her eyes not quite meeting mine. ‘Something I saw on Andrew’s phone.’

My heart starts to race. ‘Go on.’

‘I should have told you, but I was terrified – you’ve seen what he can do – and if you questioned him, he would have known it was me who told you.’ Desperation flickers in her eyes before she glances away to make sure Niamh can’t hear. ‘But he had a photo on his phone – an indecent photo of a young girl. I challenged him and he made it sound like it was nothing.’

‘How young?’ My voice is sharp.