The Ghost Tree: Gripping historical fiction from the Sunday Times Bestseller. Barbara Erskine

Some good fresh air was what the boy needed to rid him of his dangerously active imagination.

      The family castle at Cardross had been sold fifteen years before by their father, and only his elder children, David, Anne and Isabella, could remember it. In David’s case, barely. Neither Henry (Harry to the family), nor Tom, the youngest, had been born. David could still picture the ruinous tower, crumbling walls, miles of wonderful countryside, forest, moorland, wild desolate bog, boating on the loch, freedom. Life in Edinburgh was one long round of constraint for all of them. Their father was charming and vague and kind to his children, preoccupied with his own interests. It was their mother who was strict. It was she who taught them all to read, progressing to Latin and then to her great passion, mathematics. It was she who held the purse strings, she who carefully and methodically eked out their meagre finances, she who, though she knew he would deny it, had persuaded her husband to sell the Cardross estates to his cousin John of Carnock, who, as a popular and brilliant professor of law at the university, earned a large enough salary to run the place. John Carnock, amongst his many other duties, quietly kept a fatherly eye on David, who was one of his students, and on the rest of the Buchan brood. His own children were grown and he pitied his cousin’s young family, cooped up in the rambling flat on the crowded spine of Edinburgh’s heart. He was only too happy to agree to David’s plea and allow the children to escape to their ancestral home for the summer.

      The Earl and Countess of Buchan still had some of their estates, the Linlithgowshire acres and Kirkhill House at Broxburn, thirteen miles from Edinburgh, but that too was ruinous and leaked, just as Cardross had done. Agnes, the children’s mother, had hated living in these ancient castles. She loved the sophisticated delights of Edinburgh’s intellectual life, with writers, lawyers, politicians, ministers of the kirk always there, taking tea, dining, discussing excitedly the matters of the moment, the concerts and the theatre. It was a huge relief to her when all that was left of Cardross to the Buchan family was the title. David, as the eldest son, was Lord Cardross; his sisters were Ladies; Harry and Thomas, much to their glee, were styled ‘honourable’.

      John Carnock sent the trio off in his coach. He knew Agnes, Presbyterian to the roots of her hair, would not have approved such luxury but he persuaded her that as he was sending a load of books and furniture to Cardross anyway it would be a favour to have David there to see them safely in place and to keep an eye on things. He was refurbishing the castle, he explained to her, and there was no one there from the family to oversee matters as he was spending the summer in town working on his latest book. David, it was made clear, would be expected to watch the builders and report back.

      No one, least of all Agnes, expected anything of the sort to happen. The moment the boys set foot outside the coach they were off into the park, laughing and shouting, David, far from keeping an eye on his brothers, a child again in his head, leading the way.

      Their first big excursion had to be to his favourite place, the loch and the island on it where Mary Queen of Scots had spent some of her childhood holidays.

      The two bigger boys rowed; Tom sat in the bow staring round him in awe. The Loch of Menteith, two miles from Cardross House, was peaceful, surrounded by low hills but with the great peak of Ben Lomond off to the west. There was a gentle breeze wafting the sweet smell of grass and heather towards them across the water as they neared the island of Inchmahome.

      From the boat they could just see the grey ruins of the ancient priory through the trees, the clouds dappling shadows over the soaring sunlit arches and broken pillars. In the distance they could see someone from the village fishing from the stern of his boat, but he was far away and paid no attention to the boys. As they drew nearer an osprey plunged into the loch alongside the boat and dragged a fish out of the water, flying away towards the west. The island itself was deserted.

      Running the boat ashore, the two elder boys scrambled out eagerly. Cousin John’s housekeeper had placed some bottles of ale into the boat for them, and pausing only to put them into the water at the edge of the loch to keep cool, the two elder boys raced ahead. David turned. ‘Come on, Tom!’ he cried impatiently. Tom was still staring through his little telescope, back the way they had come. He stowed it in his bag and climbed out onto the grassy bank. His brothers didn’t wait for him; they were used to him dawdling behind, his attention taken by every new bird and plant and dragonfly. He had a small notebook which went everywhere with him; in it he would make laborious drawings and sketches of everything he saw, drawings which even David had to admit were not bad.

      Slinging his bag over his shoulder, he made his way after David and Harry along the track towards the ruins of the old priory. The stone arches stood out above the trees, beckoning him on as he followed sturdily in his bothers’ wake, pausing to watch the red squirrels chattering angrily in the sweet chestnut trees and a heron standing motionless near the water’s edge. He dropped further and further behind the others as they raced ahead to explore the ruins, climbing over fallen trees, watching the dragon-flies that hovered over the crystal-clear water of the loch.

      He was slowly catching up with them at last when he realised they were not alone. A man in a long black woollen robe was walking under the arch where the west door of the great church had been. Tom stopped, half shy, half scared. They had every right to be there, he knew that, but there was something about the man and his intense self-absorption which excluded the outer world absolutely. He was praying, Tom realised, and completely unaware of their presence.

      He watched as the figure walked slowly away from them into the shadows and disappeared. Only when he could no longer see him did he call quietly, ‘Was that a monk?’

      David had scrambled up onto the wall of the ancient building, sitting in a window embrasure, his back against the warm stone, his eyes closed against the sunlight. It was Harry who stopped in his tracks. ‘Where?’ He swung round.

      ‘There. He walked up that way.’ Tom was suddenly flustered. ‘We shouldn’t go after him. I think he was praying.’

      David sat up and stared round. ‘Where? I can’t see anyone.’

      ‘Are you sure you saw someone, Tom?’ Harry studied his little brother’s face. All three boys had caught the sun as they rowed across the loch, their hair tousled in the wind, and Harry’s eyes were bright with laughter. ‘It wasn’t one of your ghosts, was it?’ he probed gently.

      Tom flushed a deep red. ‘No. He was there.’ He dropped his bag on the ground and ran to the arch where he had seen the man walking away from them along the nave that was no longer there. The place was deserted; long grasses grew amongst the stones. A bird flew up as he approached, calling in alarm.

      ‘Oh, Tom, for goodness’ sake!’ David, ever scornful, allowed a cruel edge into his voice. ‘You and your ghosts! They’re all in your head, you know. You’ll be sent to an asylum if you go on like this.’ Nevertheless, he looked round with a shiver and it wasn’t very long before he suggested they go and find their food. As he and Harry made their way back towards the beach where they had left the boat, Tom hesitated, hanging behind, and as his brothers’ voices grew fainter, he realised he could hear the monks chanting, the sound rising and falling in the distance above the rustle of the trees and the lapping of the water on the shore. He felt the hair standing up on the nape of his neck and, terrified, he turned and ran after them.

      They retrieved the bags of bread and ham and cheese and pulled the bottles of ale out of the water. Tom, still chastened and embarrassed by David’s scorn and unsettled by what he had heard, sat a little apart. He was determined not to cry. He knew his elder brother could be nasty; it was Harry who was kind and patted him almost paternally on the shoulder as he came over and, cutting off a chunk of cheese with his dirk, gave it to him with an apple.

      Tom took a deep breath. ‘Why did Papa sell Cardross?’ he asked Harry. He had found himself a nook in the stones of an old wall from where he could watch the jackdaws squabbling on top of the broken arches behind them.

      ‘He needed the money.’ Harry had already started to share out the rest of the food.

      ‘Mama is always talking about money,’ Tom followed his train of thought doggedly. ‘Are we very poor?’