‘More like a double bluff,’ Grace replied, with a smile. ‘Threw you right off the track, didn’t I?’

‘I’d still have found it without you.’

‘Yeah, I’ll bet you would’ve.’

The field gate was open. Ben slowed for the entrance and drove on through, following a set of fresh tracks that cut across the open ground towards the trailer. It must have been years since the field was in any way tended. Under the layer of snow and ice the ruts and holes were rock hard, making the Mercedes lurch and bounce. Three sides of the plot were open, the fourth a thick line of trees at its eastern perimeter. There were no other houses or vehicles in sight within the wide expanse of whiteness.

As they drew closer to the trailer home Ben could see the mess of junk lying all around it. The fresh tyre tracks led up to McGlashan’s Subaru, which was parked with its front end up close to a stack of old gas bottles and other detritus. The trailer home itself was raised on blocks with a set of rusty metal steps leading up to the door. Its roof was layered with four inches of snow, like everything else around except the car, which was only lightly dusted with fresh flakes. If McGlashan was home, he hadn’t been home for more than a few minutes.

Ben pulled up behind the tail of the Subaru, blocking it in lest its owner get any ideas about trying to escape. He was half expecting the poacher to come bursting out at any moment, but there was no movement. He killed the engine, said, ‘Right then, let’s go and say hello,’ and swung open his door.

Ben was stepping out of the car when two things happened.

The first was the terrible, wailing scream that came from inside the trailer. For a split-second Ben froze where he stood and locked eyes with Grace, who was climbing out from her side. She stared back at him, her face tightening into a hard frown. Each of them thinking the same thing. Each recognising a sound that Ben had heard before, and which Grace hadn’t, but which the human brain is naturally hard-wired to identify as the cry of a fellow human in extreme, off-the-charts agonising physical distress. The same awful sound that mankind’s primitive ancestors learned as their signal to run for their lives when one of their number was suddenly clasped in the jaws of an attacking cave bear or sabre-toothed tiger.

The sound of pressing, ultimate, primal danger.