Porter didn’t dignify it with a response, pushing past them, breaking into a trot as he headed over to the right flank. A chaotic symphony of sound masked his steps, layered over the incessant hum of a busy warehouse: the thunk of a crate or pallet dropping into place, the monotonous beeping of a reversing forklift. They would cover his approach, but it worked both ways, his ears failing miserably to filter out the white noise, leaving him with nothing useful.

Porter reached the far wall ahead of Styles and turned to check the others were in place. A hundred yards away, Whittaker raised his arm, giving him a thumbs up. The shrunken figures of Carmichael and Palmer followed suit. Porter returned the gesture and they set off at a brisk walking pace, slowing down as they reached each junction, glancing along, seeing only familiar faces of other officers, and moving on.

From his brief glance up the wide valley of a central aisle that carved the building in two, Porter had seen that it ran the full length of the structure, smaller aisles feeding in from left and right like tributaries. Up ahead, an orange forklift proudly held a crate high above its body, an offering to the shelf above. The driver, unaware of the approaching officers, lowered it gently onto a ledge twice Porter’s height, backing away, fork lowering like a retreating servant bowing to its master.

Movement to his left. He spun around, nervous energy coursing through him, but it was only Whittaker waving an arm to attract his attention. Had he seen something? Porter took a few steps towards him before Whittaker called out, ‘Clear.’ He pointed ahead.

Porter stared for a second, then realised the waving had simply been to attract his attention. He had been staring at the forklift and Whittaker must have thought he’d spotted something or someone. Porter cursed his own stupidity and gave himself a mental slap. He couldn’t afford any distractions.

There was a chance, he conceded, that Bolton had made it out of the building. There could be any number of fire exits or other doors ahead. He would have to put his faith in the others who had stayed outside to check the perimeter. He prayed that wasn’t the case, and that Bolton and Stenner were somewhere up ahead. He had the utmost confidence in those outside; his hope, his need, for Bolton to be inside was purely selfish. He wanted the confrontation. Instinct and adrenaline were in the driving seat now, a hunter and his quarry.

Lurking behind that desire to call him to account for his actions was a voice that whispered of the blurred lines between justice and revenge; to hit back against a bully who had hurt, maimed and worse. Porter only hoped he could keep the voice to a whisper when the time came.