Fox, who had been on his phone, stood up and started snapping his fingers, gathering everyone’s attention. ‘Hang on,’ he said into the device, ‘I just want to put you on speaker.’ Then, to the room at large, ‘They’ve just patched me through to the driver who picked him up from Till’s.’ Having dabbed at the icon for the phone’s speaker, he held it in front of him and walked into the centre of the office.

‘You were saying you didn’t take him very far, Mr Bishop?’

‘It was supposed to be Leith,’ the broad local voice boomed. ‘That’s a good fare any time of day.’

‘Did he specify Constitution Street?’

‘Just Leith to start with. Told me he’d decide nearer the time where to stop.’

‘So then what happened?’

‘We’d hardly got any distance at all, and he started saying he wanted chips. I mentioned two or three places we’d be passing, but he didn’t want to wait. Said he’d get out right there and find somewhere.’

‘There being …?’

‘Corstorphine Road. Like I say, he’d only been in the cab two minutes.’

‘Whereabouts on Corstorphine Road?’ Fox had taken a couple of steps towards the murder wall, where a street plan of the city had been pinned up. He was joined by Esson and Clarke.

‘Just by Howson’s – it’s a wine bar. I was worried he might head in there, but he didn’t. Man was a gent, mind.’

‘How so?’

‘Gave me a nice crisp twenty – joked that he’d printed it himself. Told me to keep the change.’

Siobhan Clarke had her finger pressed to the spot on the map where she reckoned Howson’s was. It was the wine bar where she’d met Gina Hendry before their first visit to see the sisters. Esson had tapped a query into her phone.

‘Nearest chippie is if he doubles back to Glasgow Road.’

‘Supposing that’s what he really had in mind,’ Clarke said ­quietly.

Fox had ended the call and was taking out his posh pen so he could mark an X next to where she was pointing.

‘Maybe he walked on towards Haymarket,’ he suggested. ‘Plenty places there.’

Clarke, however, was tracing a route with her finger from Howson’s to Stephanie Pelham’s house.

‘Five, maybe ten minutes it would have taken him,’ she said, more to herself than anyone else.

‘We’d know if he’d been back there,’ Esson commented.

‘Maybe there was no fuss this time. Just a man full of alcohol whose wife had promised him they’d talk.’

Esson was shaking her head doubtfully as Clarke retreated to her desk to pick up her ringing phone. It had stopped by the time she reached it. Caller ID: Ronnie Ogilvie. She tried calling him back, but it went straight to messaging, meaning he was probably already talking to someone else.