Parrish and Farrell leaned over to inspect it. ‘It’s a turd, yes,’ said Parrish. ‘Have you never seen one of those up close, either?’

She was horrified. ‘But . . . it’s on the pavement.’

‘It’s the late 20th century, Lockland. Society was breaking down. People probably crapped on the pavements all the time.’

‘It’s only a dog turd,’ said Farrell, taking pity on her. ‘No one’s squatting in the street.’

Luke sighed and shifted his weight. ‘Can we just get this over with, please. Blonde. Sure thing. Tonight.’

‘It’s all very pungent,’ said Lockland, walking wide around the alleged dog poo and sniffing the cocktail of exhaust fumes, wet pavements and burning rubber.

They stopped outside Number Seventeen and peered up at the sad house. The curtains drooped. The paintwork was peeling. At one point, someone had tried to tame the small front garden by hurling a ton of gravel on it. Weeds and coarse grass had found the strength to overcome this attack and flourished triumphantly. The front gate hung from only one hinge. The hedge was old and straggly. More unrecognisable loud music pounded from the open bedroom window.

Lockland suddenly felt a twinge of sympathy for Henry Plimpton. Who wouldn’t want to escape this?

‘Number Seventeen,’ she said, bringing up the information on her scratchpad. ‘The pod says this is the residence of Henry Plimpton. One wife. One son. One daughter. All resident.’

‘Listen up, everyone,’ said Parrish, as they negotiated the wonky gate. ‘I’ll do the talking.’

‘No,’ said Farrell, in disbelief. ‘Will you?’ Jane stepped smartly between them.

Luke led them up the path. ‘Stay behind me, team, and be ready for anything.’ He rapped sharply on the front door.

They might have thought themselves ready for anything, but all three were completely unprepared for the great blast of noise as the front door opened.

The enormous woman in front of them appeared to be singing. ‘. . . But don’t look back in anger . . .’

‘What?’ said Parrish in disbelief, but whether he hadn’t heard or simply did not comprehend was not clear.

Two ratty mongrels raced down the stairs, hell-bent on defending their property to the death. In the way of small, irritating dogs everywhere, they bounced into the air, yapping furiously. In the way of small, irritating dogs everywhere, they also wagged their stumpy tails, presumably in case the visitors had biscuits in their pockets and were feeling generous.

The AI hadn’t mentioned dogs. Parrish took a deep breath. ‘Madam, we are the police.’ A phrase he thought successfully juggled truth with enough impact to install the fear of God chez Plimpton.

Sadly, he failed on both counts. The woman simply stared at him and then shouted, ‘What? I can’t hear you. Shut up, dogs. What?’

No one noticed the small drone high above them. Back in the pod, Ellis and North were staring at the screen, coffee forgotten.