Jack rolled his eyes. ‘I was interested right up to the point where you said “upload”.’

Gwen tutted. ‘All the SOCOs I know would love that kind of system. Something that could identify patterns that link directly to individuals. Like persistent offenders whose patterns of offence haven’t been obvious to investigators.’

Jack grinned at her. ‘Oh, you and Tosh were just made for each other.’

A breeze was starting to lift litter down the narrow alley, and swirl it around their feet and onto the corpse. Sweet wrappers stuck in the blood and vomit.

Gwen studied the sky. Dark grey clouds were obscuring most of the blue now. ‘Weather’s deteriorating.’

‘Yeah,’ said Toshiko’s voice. ‘There’s a strange cold front over the city. Not what we’d expected from the forecast. Plenty of rain on its way, and the temperature’s unusual for this time of year. Low 60s. Like Owen’s IQ.’

Jack pulled his collar up as the breeze stiffened. ‘OK, Tosh, your smart system has had plenty of time now. So where’s our killer?’

‘Already left his office. Office mates said they thought he was going into the city centre, not back home. Then we lost his trail behind a lorry on the M4, and missed his exit junction.’

‘Options?’

‘I’m trying to get to his secretary,’ said Toshiko. ‘And we’re still scanning for his car.’

Jack considered the corpse at his feet. ‘All right, Gwen and I are going into the centre. Tosh and Owen, we need clean-up here for the corpse. Location…’

‘Got it from your GPS signal,’ Toshiko said. ‘Post code CF24 9XZ. You’re in Gwion Lane, Splott.’

Jack broke the connection, and started back towards the SUV. Mitch had got to his feet now, and stood to an awkward kind of attention as Jack and Gwen approached. This meant he stood between them and the Torchwood car.

‘I radioed for back-up, and they’re on the way. Until then, anything I can do to help, sir?’