Patrick shook his head. ‘No, Graham. Why don’t you put down the matches? Then we can talk.’

A small smile. ‘No, we’re going to talk anyway.’ He coughed. ‘You think I’m a murderer, don’t you?’

Patrick didn’t respond. He waited.

Graham pointed a finger at him and Patrick noticed that it was shaking, his body betraying his nerves, the tension. ‘I’m not a murderer. Not a criminal. I killed those girls, sure, but it was justice.’

‘Because of Melanie,’ Patrick said gently.

‘Yes! Those bitches . . . those fucking little bitches murdered her.’

‘She killed herself, Graham. I understand how hurt you must have been. Your friend.’

‘She was more than my friend! She was my soulmate’ – he laughed crazily – ‘my whole world. I promised her that I’d always protect her.’

‘You didn’t do a very good job, did you?’ Mervyn said.

Graham swung around, pulling a match from the box. Mervyn shrank away. ‘It wasn’t my fault. She didn’t . . . She never told me what was happening.’

Guilt. That was what was driving this, Patrick realised. Graham knew he should have been aware of what was happening on the forum that he managed. He wondered if there was more to it, if Melanie had only been into OnTarget because her boyfriend worked for them.

‘It was those little bitches’ fault,’ Graham hissed, turning back to Patrick. ‘The things they said about her . . . She was so sensitive, so vulnerable. She couldn’t take it. She was a beautiful person. I looked out for her at St Mary’s. And afterwards, I always kept in touch with her, helped her, even when . . . even though we couldn’t be together anymore.’

‘Why not?’ Patrick asked in a soft voice. ‘Why couldn’t you be together?’

‘Because she didn’t want me anymore. She wanted them. Those fucking . . .’ He breathed deeply. ‘OnTarget. She retreated into a fantasy world, thought that Shawn and the others were in love with her, that they were going to save her. Suddenly, I wasn’t good enough anymore. I stopped going to see her for a while. It all seemed so cruel. It was me who got her into OnTarget. Me who was supposed to run the forums she was so interested in, that she spent all her time on. I didn’t look at any of her posts on the forum for weeks because it made me feel too sick, knowing she was on there talking about her new great loves.’

Patrick was surprised. After talking to the staff at St Mary’s he had assumed that the love between Graham and Melanie had been one-way: the boy who longed to be wanted loving the attention he got from the vulnerable girl who worshipped him. But it seemed that Graham loved Melanie too. It made sense. Graham had been abandoned, thrown into the care system. He had been vulnerable too.

But that didn’t mean Patrick felt sympathy for him.

‘You tried to frame Shawn, didn’t you?’ Patrick said. ‘Asked Hattie to tell me about him and that Irish girl.’

Graham didn’t reply. He just smiled slyly.

‘And then you tried to frame Mervyn, leaving the underwear at his house, calling us.’

Another smile.

Burns still hadn’t told Patrick what he wanted and why he had brought him here.

‘Let’s talk,’ Patrick said. ‘Tell me how I can help you.’

Graham gathered himself, but still held the match between his trembling fingers. ‘I want the true story made public,’ he said. ‘My side of the story. Melanie’s story. I need him to call his friends in the press, make it happen. I want a full interview, front pages, my words with no censorship. I want the world to know that Melanie – the real Melanie, the one who loved me – was pure and innocent, and that I was only granting her dying wish: retribution against the bitches who killed her. Justice. Melanie’s soul is in torment right now. I can feel it. I thought that the only way Mel could find bliss in death would be for her tormentors to suffer and die. But if that can’t happen, if one of them lives, then the only way to stop her suffering is to make sure the world knows the truth.’

‘I can do that,’ Mervyn said. ‘Just give me my phone back and I’ll call the editor of The Sun right now.’

‘But why do you want me here?’ Patrick asked, having a horrible feeling he knew what Graham was going to say.

‘You’re going to vouch for me, back up my story. Speak to the journalists, tell them I’m not guilty of any crime. You need to tell them I did the right thing.’ He shouted the final words, his face contorted. ‘And you need to arrest Chloe Hedges for murder.’

Patrick kept his voice even, neutral. ‘I can’t do that, Graham.’

Graham took a step towards Hammond and placed the head of the match against the side of the box.

Hammond struggled on the chair, rocking from side to side, almost tipping it over. Patrick moved towards Graham slowly. Could he grab him before he struck the match? It was too risky. Better to talk. It seemed pretty clear that Graham hadn’t thought this through. Not unless he planned to keep them here all day and night until he saw a copy of the next morning’s newspaper. And how was Patrick supposed to arrest Chloe, while he was stuck in a barn full of petrol?

‘Graham,’ he said in a soothing tone. ‘We can get you help. Maybe . . . maybe we can help organise a memorial for Melanie. Set up a foundation in her name against Internet bullying. Whatever you want. But Chloe Hedges is innocent, just like Melanie was. And what about Nancy Marr? You killed her too, didn’t you?’

Graham’s eyes flashed. Did he think he’d got away with that one?

‘What happened, Graham? Did she find Melanie’s body? And the suicide note?’

The other man clenched his jaw.

‘And you decided on the spot to kill Nancy because you didn’t want anyone to know why Melanie had committed suicide, so you could get revenge without anyone seeing the connection between the victims?’

Graham’s silence told Patrick his theory was correct.

‘And you practised your torture method on her . . .’

‘She told me it was my fault!’ Graham yelled. ‘That I should have been keeping an eye on Melanie, should have known what was going on. She was an interfering old bitch, just like all the interfering bitches at St Mary’s!’ Spittle sprayed from his lips. ‘I’m sick of this!’ he roared and it was as if something snapped in his head, the final thread of self-control. He loomed towards Mervyn.

‘Don’t do this, you’re my son!’ Mervyn yelled.

Graham stopped, the unstruck match only inches from Mervyn’s skin. Patrick was terrified the petrol fumes would ignite. He couldn’t wait. While Graham was momentarily distracted, Patrick launched himself at him, knocking him down, both of them falling to the ground, which was slick with petrol. Graham jumped to his feet and as Patrick tried to stand he slipped and fell to his knees. Graham stepped forwards and kicked Patrick in the face, the explosion of pain sending him reeling.

‘You’re lying,’ Graham said, producing another match from the box. ‘Always lying. It’s what you do for a living.’

Patrick sat up. His clothes and hands were covered with petrol. Graham was holding the match but was shaking so hard now that he couldn’t strike it, cursing and muttering with frustration while Hammond begged him not to do it.

Patrick needed to get Graham away from Mervyn.

He stood up. ‘Your girlfriend deserved to die,’ he said.

Graham’s head whipped round towards Patrick, mouth opening, eyes flashing with shock.

‘She bullied those girls – Chloe and Jade and Rose and Jess. She got what was coming to her.’

‘Don’t. Say. That.’

‘I’ll say what I like, Graham. I don’t give a toss if you turn Mervyn here into a human flambé. He’s a scumbag. Go ahead, torch him. Do the world a favour. But after you do I’m going to tell the whole world what Melanie was really like – a girl in her twenties who was obsessed with a fucking boy band. An ugly, weird freak.’