Today, though, the sun was shining, and the honeyed air was still and sweet. Summer seemed to have arrived at last, and Andrew couldn’t imagine any hint of evil taking place.

The deepest part of the tarn ran closest to the road, and a tall, solid drystone wall separated it from children and drunks and anyone else foolish enough to wander around up there in the dark. To get access to the water, you had to drive a few yards farther on, cross the stile and take a footpath that led to its shallow shore. In the days before the government restrictions, it had been a popular spot for ramblers and picnickers, but these days it was off-limits, except to people such as Andrew. A government poster nailed to the stile warned people to stay out on penalty of a steep fine.

Before heading out with his dinghy and his sample jar, Andrew sprayed his Wellington boots with disinfectant and donned his plastic outerwear. He felt like a spaceman preparing for a walk on the moon. He also felt hot inside the protective clothing, and all he wanted to do was get this over with as soon as possible, then head home for a nice long bath and an evening out in Northallerton with Nancy, maybe the pictures, a spot of dinner and a drink after.

Feeling the sweat drip down the back of his neck, he walked along the narrow dirt path the hundred yards or so to the edge of the tarn and squatted by the waterside to fill his sample jar. It was so quiet up there, he could imagine himself the only man left in the world. Because he had to take samples from various depths, he got in the small dinghy and began to row. The tarn wasn’t much bigger than a large pond, maybe a couple of hundred yards long and a hundred wide, but it was quite deep in places. Andrew felt a little disquiet at being out there all alone, not another soul in sight, and whenever he looked down into the water he fancied he could see a roof or a street below. It was an optical illusion, of course, most likely caused by the sun on the water, but it unnerved him nonetheless.

When he neared the wall, he noticed some dark material snagged on the roots of an old tree. The tree was gone, but gnarled roots still jutted out of the bank like arms reaching out of a grave, and there was something about their arched, sinewy shapes that upset Andrew even more. Curious about the material, however, he put his fears aside and rowed closer. Legends and myths couldn’t harm him.

When he got near enough, he stretched out his arm and tried to free the material from the root. It was heavier than he thought, and as it jerked free, the dinghy tipped and Andrew, off-balance, fell into the tarn. He was a strong swimmer, so drowning didn’t worry him, but what chilled his blood was that the thing he was holding tightly as a lover in a slow dance was a dead body, and from its ashen face, open dead eyes looked directly into his.