‘No. Turns out it’s a fairly unusual item. This took some research on the lab’s part, so I think we owe them a favour. But they say it’s a Romanian military sniper rifle, the Pusca Semiautomata cu Luneta, or PSL. It might be considered to belong to the Kalashnikov family, but it’s different in appearance.’

‘Well, one thing’s for sure. Nobody’s going to admit to owning such a gun. There’s a mandatory five-year prison sentence for the possession of an illegal firearm.’

‘It’s probably a clean weapon anyway. It won’t be easily traced back to its origin.’

Hitchens nodded. ‘As for Simon Nichols – or Simcho Nikolov, I should call him – we haven’t yet received the full post-mortem report, but so far there is no evidence that his death was due to anything but natural causes, or an accident.’

‘So he probably isn’t a victim? In that case . . . ?’

‘Yes,’ said Hitchens. ‘We should be regarding him as a potential suspect for the Rose Shepherd killing. We need to find some way of establishing his movements in the last few days before he died.’

After the briefing, Cooper found himself standing in the corridor with Liz Petty. Some mysterious force seemed to place them together at unexpected moments. Or perhaps that was only the way it seemed.

‘Are you OK?’ he asked.

‘Yes, fine. Thanks, Ben.’

When he spoke to Liz on the phone her voice always sounded so warm that it took him by surprise, almost knocked the feet from under him. Many female police officers formed a hard exterior, but not SOCOs, it seemed. He’d have to be careful not to make a nuisance of himself phoning her too often, just to hear her voice.

Petty seemed about to touch his arm, but drew back suddenly and looked past him, over his shoulder.

‘Uh-oh.’

‘I was asking Liz about the search at the caravan,’ said Cooper when he saw Fry approaching.

‘That’s OK.’

‘She just happened to be passing, and I –’

‘It’s all right,’ said Fry as she drifted by. ‘I don’t care. See you later.’

They both watched her disappear down the corridor.

‘What’s up with her?’ said Petty.

‘I’ve no idea.’

‘Perhaps she’s turning human.’

‘I’d better get on anyway,’ said Cooper uneasily. ‘There was one thing I wanted to ask you.’

‘Yes?’

‘Do you think it would be possible to find out more about this weapon that fired the shots at Bain House, the PSL sniper rifle? I know the lab have pulled out the stops for us, but could you have a word with Wayne?’

‘I’m not sure, Ben. What do you want to know?’

‘Whether there are non-military versions of it.’

‘OK,’ said Petty. ‘I’ll see what we can find out.’