‘Absolutely. If we can establish why Rose Shepherd was in hiding, it should give us a lead on her killer. At the moment, she’s still something of an enigma. But that was all her own doing. In making it difficult for anyone to find her, Miss Shepherd also made it harder for us to identify her murderer.’

After the meeting, Cooper collected the actions he’d been allocated on the enquiry, then went straight to his computer. He Googled the Matlock Bath webcam and soon found the site. Life in a Lens, that was the name of the photography museum. The camera seemed to be mounted on the roof.

According to the caption, the webcam picture was updated every sixty seconds on weekdays, but it seemed to be more like thirty seconds when it began to reload. The picture was pretty grainy, of course. They’d have a hard time identifying anyone, unless there was detailed information available about what they were wearing at the time.

Matlock Bath was a bit like a seaside resort, but without the sea. Beyond the railings to the right there was just the shallow water of the River Derwent. The camera covered only a section of the road and the river beyond it. This was North Parade, looking northwards to Jubilee Bridge. But the picture showed almost nothing of the shops and cafés on the promenade, except for a glimpse of some buildings in the background.

It was a grey, damp day in Matlock Bath. The river was brown and choppy, and Cooper could see mist hanging on the slopes of the narrow valley. Cars and people were reflected in the wet tarmac of North Parade.

Fry stopped to look over his shoulder. ‘Is that Matlock Bath?’

‘Yes.’

‘It looks pretty miserable.’

‘It’s one of those places that changes completely at weekends, or in the summer. On a busy bank holiday, you wouldn’t recognize it.’

‘I’ll take your word for it.’

Cooper looked up at her. ‘Diane, do you think the internet is how Rose Shepherd created a social life for herself?’

‘It’s beginning to look that way, isn’t it? Why?’

‘I always find that a bit sad. I don’t think the internet was ever intended to replace social contact, only to make communication easier for people who were isolated from each other.’

‘As far as we can tell, Miss Shepherd was isolated,’ said Fry. ‘It’s just that she’d cut herself off deliberately.’

‘I can’t even begin to imagine living like that,’ said Cooper. ‘I’d get desperate very quickly.’

Fry reached for her phone as it rang. ‘It looks as though Miss Shepherd must have been a pretty strong-willed, self-sufficient woman, don’t you think?’