Nell put her hand on the door and a boot into the hall. ‘That’s OK, we’ll wait while you wake her.’

Ten minutes later Joanne appeared, dishevelled and bleary-eyed, wrapped in a blanket.

‘Hello, Joanne,’ Nell said. ‘We’d like to ask you about a phone call made to your house on the night Connor O’Brian was killed.’

Ian glanced down at Joanne. It looked innocent enough, but Nell knew it was a question, one that told her he wasn’t the one who had taken the call.

‘Joanne,’ she asked, gently. ‘Did somebody phone you the night Connor was killed?’

Joanne didn’t move; it was as if she couldn’t even hear them. Nell looked to Ian.

‘It’s hard for her to have you here. The trauma of the last few years is still very real and we’ve barely undergone therapy for it.’

His tone was gentler than before and Nell nodded. Leaning forward, she tried to catch Joanne’s eye.

‘Joanne,’ she said softly. ‘We don’t think you did anything wrong. We think the killer has involved you in this by mistake. I know you want to avoid all mention of it and pretend it didn’t happen. And I understand you don’t trust us, but if you know anything at all about that night, please tell us.’

Nell thought Joanne was about to cry, but the woman surprised her by wiping her face with the palms of her hands before sitting upright.

‘Someone did call here.’ She ignored the questioning look from her husband. ‘I don’t know who it was. They hung up before I could speak to them.’

‘The thing is, Joanne, we know the call lasted three minutes. So, are you telling me the call was just three minutes of silence?’

Joanne opened her mouth to speak, then shut it. Ian stared at Nell, his arm still around his wife.

‘Can you tell me what relevance this has to anything?’ he asked.

‘The killer called the victim and one other person – that other person was your wife. I’d say that was pretty relevant, wouldn’t you?’

When he didn’t answer, she turned back to Joanne. ‘Was the woman who rang you called Mary?’

Joanne’s head shot up. ‘Why do you ask that?’

‘Why don’t you answer that?’ Nell replied. ‘Do you know someone called Mary?’

‘No.’

‘Was the woman who contacted you on the night Connor was murdered called Mary?’ Nell repeated.

‘No.’

‘Are you working with Mary?’

Joanne gave a small laugh. ‘Working for what?’

‘I don’t know, I’d hoped you’d tell me that. Maybe you want to frame Ms Graham for Connor’s murder?’

‘No.’ Her tone was one Nell imagined she’d learned in prison: hard, defensive.

‘But you do want to pay back Ms Graham for what you consider a miscarriage of justice?’