‘He couldn’t have done that, Melissa. Oliver is a lot of things, but not a murderer. He took the flak for me. And anyway, he wouldn’t have had time to kill her and bury her – he was back at my house less than …’

‘Less than what?’

‘I – I’m not sure exactly, but he hadn’t been gone long. I was beside myself with worry, but I would remember if I’d been waiting ages for his return.’

‘And you have a clear memory of everything that happened that night, do you? You weren’t panicked? Confused?’

‘Well, I …’

‘So you might not remember the time he came back. An hour, two, may have passed. Can you be one hundred per cent sure he was back within half an hour? And anyway, I’m sure it didn’t take long for the sick bastard to end her life.’

‘No. I guess you’re right.’ Louisa’s head shook involuntarily with shock, yet also an element of relief, as she attempted to assimilate this new information. ‘I just can’t believe it. I thought it was me. That I’d killed her. I can’t understand why Oliver would tell you now, though.’

‘Guilt. It’s what made him seek me out in the first place. He’d murdered my sister, with his bare hands, and then dumped her body. Covered it over with earth, leaving her to remain undiscovered for however many years – forever if he was lucky. Ensuring her family never got closure. It wasn’t until the night of your party, when I finally confronted him, that he dropped the pretence. He never really loved me. I was just his act of atonement. He tried to make amends for his actions by being there for me, supporting me, but of course, he couldn’t have ever told me the real reason he’d asked me out before – the reason he’d asked me to marry him – or he’d have lost me. I was his only source of redemption. He’d been willing to keep his hideous secret, the real reason he was with me, from everyone. And if it wasn’t for me coming here, meeting you, he’d likely have succeeded.’ She tutted and looked away.

‘Why would he make me believe that it was me?’ A surge of pain, hot, seared inside her stomach. ‘Did his feeling of guilt not reach as far as me?’

‘He saw an opportunity I imagine. Thought he could finally offload the guilt onto you. Then he’d finally be able to get on with his life. With the sister of the woman he murdered. Makes me sick.’

‘So your disappearance …?’

‘I was angry, hurt. Mentally and physically. I had to get away from him. But I wanted to make him pay. Make you pay as well.’ She smiled thinly. Louisa opened her mouth to speak, to put up some sort of defence, but no words came out.