The gold coin seemed to glitter between his fingers with a life of its own. Ewan had never seen anything like it before. He turned off the hoover and sat at the wheel of the van to examine the coin more closely. Its markings were ingrained with dirt, as though it had not long ago been dug up out of the ground. But they were still clear enough for Ewan to make out. One face bore the head of a regal-looking individual with long, flowing locks of hair and a noble, patrician profile. Inscribed around the circumference were the letters LVD.XV.D.G.FR. ET NAV. REX. The reverse of the coin was inscribed with a crown and more writing: CHRS.REGN.VINC.IMPER.1746.

None of which meant anything to Ewan except the obvious 1746 date mark. And the fact that it was most definitely not a piece of brass. But now the question was burning inside him: what on earth had Ross been doing with it?

On an impulse, he got out of the van, knelt down by the open driver’s door and reached an arm under the seat to see what else might be under there. To his even greater amazement his fingers closed on a second coin. As with the first, he stared at it for a long moment. It was virtually identical except for the date mark, which was a year older.

Where could Ross have possibly found these? Surely, not even an inveterate slob would leave valuable gold coins lying around for any length of time in their car. They couldn’t have been here long. Perhaps this explained where all the mud had come from. Was this what Ross had been doing on his trips into the countryside, rooting up old coins?

Scotland as a whole was incredibly rich with history, but nowhere more so than this region. Myths and legends of buried treasure had for years drawn legions of dreamers and speculators to the Loch Ardaich pine forest and surrounding glens looking to get rich in other ways, armed with metal detectors and shovels and divining rods and God knew what else. Nobody had ever found anything of significant historic interest, barring a few rusty old arrowheads and, on one exciting occasion, a medieval Scottish claymore sword so decomposed that it looked like a rotted stick. Gradually, the treasure hunters had dwindled to a bare few – while the sceptics and naysayers became both more numerous and vociferous. ‘There’s nothing there’ had become the received wisdom.

But it looked as though Ross might well have proved the naysayers wrong. Why hadn’t he shared the news of his discovery?