The two patrol cars slid quietly through Rissington Common as the first predawn light was beginning to seep over the horizon. There was no traffic, and no one about. The vehicles eased their way down Bourne Lane past the Tickett yard on the left, and beyond Willow and Dove cottages on the right. The first fingers of rosy dawn silhouetted the spire of St Crispin’s church. In the second car, Gillard was looking at his iPad, on which their GPS position was marked relative to the fixed point of the last known position of Arrowsmith’s watch. The two dots were almost in eclipse. Next to him, DC Michelle Tsu had an iPad with the dynamic map on it. There was no change in position, no fresh signal.

A uniformed officer from the first car opened the gate into the meadow, and the two vehicles trundled across the uneven grassland until they reached the high embankment on which the excavator still stood. Gillard magnified the map as far as possible, which indicated that they still needed to go further east, deeper into the meadow. ‘At the other end of this is Rissington Lock, but that’s more than half a mile away. I think we need to go on foot from here.’

Five uniformed officers led by a sergeant joined the two detectives, leaving one PC with the cars. They began on the embankment, whose firm stony surface was easier underfoot than the overgrown and soggy meadow. After 200 yards, Gillard stopped them and cross-checked his map with that of DC Tsu. ‘It looks to be about here,’ he said.

‘Well that’s it,’ said the sergeant, shining a powerful torch across the ground. ‘He’s dead and buried, somewhere here.’ Michelle Tsu nodded her agreement.

There was already enough light to see their footing, and Gillard descended from the embankment. ‘This looks like part of the earlier excavation,’ he said. ‘The vegetation hasn’t fully regrown.’

‘The dog handler should be here in half an hour,’ the sergeant said from the top of the embankment. Gillard had requested a cadaver search dog, which was being driven over from Kent. In the meantime, he could do his own searching. The detective crouched down and shone his torch, moving along the compacted plant-free soil which marked a recently buried pipe. He spent five minutes edging along the scarred meadow, while his colleagues watched him.

‘There’s an inspection cover under here,’ he said. He took some photographs on and around the metal plate, which showed that someone had carefully spread fresh earth around to hide it. Michelle and the uniformed cops joined him, and traced the 3’ x 2’ lid set in a concrete surround. Gillard knelt down on it and with the metallic shaft of his torch tapped against the metal plate. ‘Anyone down there?’ he called.

He pressed an ear against the cool manhole cover. There was no sound except an echoing drip.