Detective Chief Inspector Craig Gillard had visited most parts of Surrey in his decades in the police, but the tiny hamlet of Rissington Common was new to him. A body had been found there by workmen, close to the River Wey. Right in the south-west corner of the county, the map had shown a thorn-shaped valley sticking painfully into the top edge of Hampshire. On this showery morning he’d taken the A286 past Haslemere, and then the new dual carriageway from Camelsdale heading towards the A272. Once off this elevated link road he followed the signs and the road soon narrowed and deteriorated, overshadowed on both sides by dense woodland. After a few hundred yards a mildewed sign announced his arrival at Rissington Common. A small triangular green divided the hamlet between a whitewashed pub on the left and a village shop on the right. The few dozen cottages he could see were all Victorian, and there were few of the signs of gentrification that the rest of the county had in spades. It was only four miles from Liphook and Haslemere, but it could have been a thousand.

Gillard eased his unmarked grey Vauxhall along Bourne Lane, past a large and untidy builders’ yard, and a dozen more cottages. The road deteriorated further as he headed downhill towards the river, becoming a potholed track, crammed with untidily parked vehicles. There were fewer homes and cars in the final 200 yards. The last house on the right was a larger rectory type with a wild garden, and on the left was a tiny stone church with a squat tower and overgrown graveyard. Beyond it, the land opened up as marshy pasture, grazed by scraggy cattle, and dotted with alder, silver birch and stands of willow.

In the distance to the left, Gillard could see the upraised orange arm of a tracked digger, and the flash of blue lights, his destination. The Vauxhall bumped and ground along the heavily rutted track until a dead-end at some bollards, and swung left through an open metal gate, avoiding the two deep muddy trenches left by the crane’s tracks. The detective gingerly steered the car across the meadow, following tyre marks, and then mounted a new crushed-stone track which led up through a dense stand of willows to an embankment at the river’s edge.

The twenty-two-ton tracked JCB excavator, atop the embankment, dominated the scene. Below it, near the water’s edge, were two water company four-wheel-drives, and a police patrol Range Rover. A group of a dozen face-masked individuals, three of them police, congregated around the water’s edge, between the stumps of two trees, staring into a large water-filled hole.