They settled down to wait, and a few minutes later heard a crunching of leaves from the direction she then came from. Porter stared at the leaves in front of him, willing them to part enough to let him watch her walk past. The footsteps grew louder, and were accompanied by snatches of colour on the other side of the bush. Porter frowned. The colours were wrong, and a second later a man wearing a light blue waterproof jacket walked past, hands jammed in pockets, strains of music, audible but not identifiable, leaking from his headphones.

Mary Locke made them wait another five minutes, her footsteps quick and light. She was past them in a flash of colour, but Porter put a hand on Styles’s arm and counted a full ten seconds before letting go and stepping out onto the path. She had already reached the junction of the five routes and Styles headed after her without a word.

Porter watched him go before turning and breaking into a jog towards the spot he’d fixed in his memory earlier. She had left the path a few yards past a large stump on the right-hand side. The relatively flat top, and absence of trunk anywhere in sight, suggested it had been felled rather than fallen; a long time ago, judging by the top, worn smooth. He glanced down the path again in time to see Styles disappear round the corner. He figured he had ten minutes before Mary Locke reached her car, so that gave him five minutes to look around if he wanted to get back in time to follow her to the cafe.

Porter scanned the trees and bushes ahead. He stood still, listening for anything that could signify another person nearby but all he heard was the faint noise of traffic in the background, punctuated by the chatter of unseen birds. As they had waited for her to pass them a few minutes ago, an idea had started to form. What if she wasn’t here to meet anyone? What if she was here to hide something, leave something behind? She had been carrying a large handbag that could have concealed any number of things, maybe something relevant to Natasha.

He looked up into the branches and slowly worked his way down. The thick canopy of leaves meant that the diluted sunshine had to work even harder to suck up any rainwater that made it down this far. There was no surface water, but the soil looked far from dry. He squatted down for a closer look, and saw the tread of a shoe in amongst the dark ridges of mud. Another, less clear, but a similar enough size to be from the same shoe, lay just ahead of it. A small shoe. A woman’s shoe. He was on the right track.