The rain grew heavier, but in the distance the sky was already clearing. It wouldn’t last long. All the same, Siobhan’s legs were soaked, her trousers sticking to her. Grant’s trainers were making squelching sounds. He had switched to auto-pilot, his eyes staring, nothing at all on his mind except reaching the summit, whatever it took.

As they clambered up the last steep incline, the land levelled off. They’d reached the summit. The rain was easing. Twenty feet away stood a cairn. Siobhan knew that sometimes hill-walkers added a rock or stone each time they ended a climb. Maybe that was how this cairn had come into being.

‘What, no restaurant?’ Grant said, crouching down to get his breath back. The rain had stopped, a shaft of sunshine splitting the clouds and bathing the hills around in an eerie yellow glow. He was shivering, but the rain had been pouring off his cagoule and on to his sweatshirt, soaking it. No use putting it on now. His denims had changed colour to a darker, dampened blue.

‘Hot tea, if you want it,’ Siobhan said. He nodded and she poured him a cup. He sipped at it, studying the cairn.

‘Are we scared what we’ll find?’ he said.

‘Maybe we won’t find anything.’

He conceded as much with a nod. ‘Go look,’ he told her. So she screwed the top back on the flask and approached the cairn, walked round it. Just a pile of stones and pebbles. ‘There’s nothing here,’ she said. She got down on her haunches to take a closer look.

‘There must be.’ Grant rose to his feet, walked towards her. ‘There’s got to be.’

‘Well, whatever it is, it’s well hidden.’

He touched a foot to the cairn, then gave a push, toppling it. Dropped to his knees, running his hands through the debris. His face was screwed up, teeth bared. Soon the pile of stones was completely flattened. Siobhan had lost interest in it, was looking around for other possibilities, seeing none. Grant thrust a hand into his cagoule pocket, pulling out the two plastic evidence bags he’d brought. She watched him stuff them under the largest rock, then begin building the cairn again. It didn’t get very high before it started to fall down.

‘Leave it, Grant,’ Siobhan said.

‘Useless piece of shit!’ he cried out. She couldn’t be sure who or what his words were aimed at.

‘Grant,’ she said quietly. ‘Weather’s closing in again. Let’s head back.’

He seemed reluctant to go. He sat on the ground, legs stretched out, arms behind him to support himself.

‘We got it wrong,’ he said, almost in tears. Siobhan was looking at him, knowing she needed to coax him back down the hill. He was wet and cold and losing it. She crouched in front of him.

‘I need you to be strong, Grant,’ she said, her hands on his knees. ‘You go to pieces on me, and that’s it finished. We’re a team, remember?’