A shrug. ‘It was easy. I left my scooter behind a hedge on the road and approached the house from the rear. It was always in the evening so they were inside and I was able to slip into the cellar without anyone knowing.’

‘And is that what happened on Christmas Eve?’ James said.

Nash nodded. ‘After Charlotte moved out, I didn’t go there very often. But I always made a point of going when I found out she was visiting. And I’d heard she’d be there on Christmas Eve.’

‘What time did you arrive?’

‘About four. Mary was alone then and Charlotte and Savage didn’t get there until much later. And Robert turned up after them at about seven.’

‘We’ve been told that Robert saw shoeprints in the snow leading to the cellar. Did they belong to you?’

‘They did. It was a stupid mistake on my part to have left them there.’

‘Am I right in saying that while you watched everyone arrive you passed the time by eating a sandwich?’

He looked surprised. ‘How did you know that?’

‘There were crumbs on the floor.’

Nash rolled his eyes. ‘Another stupid mistake.’

James felt his pulse quicken as he asked Nash to describe what led to the killings.

Nash began with the same account as the one Neil Savage had given them. Charlotte received a call from her friend Heather Redgrave who told her that Savage had been unfaithful. Charlotte then confronted Savage and threw a wine bottle at him. Her father came rushing into the house and made Charlotte go upstairs. That was when Robert mentioned the footprints in the snow.

‘I thought he was going to come to the cellar, but then Charlotte came tearing down the stairs holding his shotgun,’ Nash said. ‘She threatened to shoot Savage who had no choice but to flee the house.’

So far so good, James thought. Nash’s description of what happened tallied with the one from Savage. Now they would hopefully get to find out what had followed Savage’s departure.

‘When we first spoke to you, Mr Nash, you came close to accusing Neil Savage of carrying out the killings. But now you’re telling us he left the house.’

‘I wanted him to be blamed because if he hadn’t cheated on Charlotte, they would all still be alive. But I have to assume now that you know he didn’t do it. I’m not proud of myself, Inspector. And it’s another reason I wish I was dead.’

James mentally crossed Savage off their list of suspects and said, ‘So now tell us what occurred in the house after Savage had driven off.’

Nash pressed his head back against the pillow and stared at the ceiling, his eyes squinting.