A moment before the encounter, a strange expectancy overcame Grady Adams, a sense that he and Merlin were not alone.

In good weather and bad, Grady and the dog walked the woods and the meadows for two hours every day. In the wilderness, he was relieved of the need to think about anything other than the smells and sounds and textures of nature, the play of light and shadow, the way ahead, and the way home.

Generations of deer had made this path through the forest, toward a meadow of grass and fragrant clover.

Merlin led the way, seemingly indifferent to the spoor of the deer and the possibility of glimpsing the white flags of their tails ahead of him. He was a three-year-old, 160-pound Irish wolfhound, thirty-six inches tall, measured from his withers to the ground, his head higher on a muscular neck.

The dog’s rough coat was a mix of ash-gray and darker charcoal. In the evergreen shadows, he sometimes seemed to be a shadow, too, but one not tethered to its source.

As the path approached the edge of the woods, the sunshine beyond the trees suddenly looked peculiar. The light turned coppery, as if the world, bewitched, had revolved toward sunset hours ahead of schedule. With a sequined glimmer, afternoon sun shimmered down upon the meadow.

As Merlin passed between two pines, stepping onto open ground, a vague apprehension-a presentiment of pending contact-gripped Grady. He hesitated in the woodland gloom before following the dog.

In the open, the light was neither coppery nor glimmering, as it had appeared from among the trees. The pale-blue arch of sky and emerald arms of forest embraced the meadow.

No breeze stirred the golden grass, and the late-September day was as hushed as any vault deep in the earth.

Merlin stood motionless, head raised, alert, eyes fixed intently on something distant in the meadow. Wolfhounds were thought to have the keenest eyesight of all breeds of dogs.

The back of Grady’s neck still prickled. The perception lingered that something uncanny would occur. He wondered if this feeling arose from his own intuition or might be inspired by the dog’s tension.

Standing beside the immense hound, seeking what his companion saw, Grady studied the field, which gently descended southward to another vastness of forest. Nothing moved… until something did.

A white form, supple and swift. And then another.

The pair of animals appeared to be ascending the meadow less by intention than by the consequence of their play. They chased each other, tumbled, rolled, sprang up, and challenged each other again in a frolicsome spirit that could not be mistaken for fighting.

Where the grass stood tallest, they almost vanished, but often they were fully visible. Because they remained in motion, however, their precise nature was difficult to define.

Their fur was uniformly white. They weighed perhaps fifty or sixty pounds, as large as midsize dogs. But they were not dogs.

They appeared to be as limber and quick as cats. But they were not cats.

Although he’d lived in these mountains until he was seventeen, though he had returned four years previously, at the age of thirty-two, Grady had never before seen creatures like these.

Powerful body tense, Merlin watched the playful pair.

Having raised him from a pup, having spent the past three years with little company other than the dog, Grady knew him well enough to read his emotions and his state of mind. Merlin was intrigued but puzzled, and his puzzlement made him wary.

The unknown animals were large enough to be formidable predators if they had claws and sharp teeth. At this distance, Grady could not determine if they were carnivores, omnivores, or herbivores, though the last classification was the least likely.

Merlin seemed to be unafraid. Because of their great size, strength, and history as hunters, Irish wolfhounds were all but fearless. Although their disposition was peaceable and their nature affectionate, they had been known to stand off packs of wolves and to kill an attacking pit bull with one bite and a violent shake.

When the white-furred creatures were sixty or seventy feet away, they became aware of being watched. They halted, raised their heads.

The birdless sky, the shadowy woods, and the meadow remained under a spell of eerie silence. Grady had the peculiar notion that if he moved, his boots would press no sound from the ground under him, and that if he shouted, he would have no voice.

To get a better view of man and dog, one of the white creatures rose, sitting on its haunches in the manner of a squirrel.

Grady wished he had brought binoculars. As far as he could tell, the animal had no projecting muzzle; its black nose lay in nearly the same plane as its eyes. Distance foiled further analysis.

Abruptly the day exhaled. A breeze sighed in the trees behind Grady.

In the meadow, the risen creature dropped back onto all fours, and the pair raced away, seeming to glide more than sprint. Their sleek white forms soon vanished into the golden grass.

The dog looked up inquiringly. Grady said, “Let’s have a look.”

Where the mysterious animals had gamboled, the grass was bent and tramped. No bare earth meant no paw prints.

Merlin led his master along the trail until the meadow ended where the woods resumed.

A cloud shadow passed over them and seemed to be drawn into the forest as a draft draws smoke.

Gazing through the serried trees into the gloom, Grady felt watched. If the white-furred pair could climb, they might be in a high green bower, cloaked in pine boughs and not easily spotted.

Although he was a hunter by breed and blood, with a Sherlockian sense of smell that could follow the thinnest thread of unraveled scent, Merlin showed no interest in further pursuit.

They followed the tree line west, then northwest, along the curve of meadow, circling toward home as the quickening air whispered through the grass. They returned to the north woods.

Around them, the soft chorus of nature arose once more: birds in song, the drone of insects, the arthritic creak of heavy evergreen boughs troubled by their own weight.

Although the unnatural hush had relented, Grady remained disturbed by a sense of the uncanny. Every time he glanced back, no stalker was apparent, yet he felt that he and Merlin were not alone.

On a long rise, they came to a stream that slithered down well-worn shelves of rock. Where the trees parted, the sun revealed silver scales on the water, which was elsewhere dark and smooth.

With other sounds masked by the hiss and gurgle of the stream, Grady wanted more than ever to look back. He resisted the paranoid urge until his companion halted, turned, and stared downhill.

He did not have to crouch in order to rest one hand on the wolfhound’s back. Merlin’s body was tight with tension.

The big dog scanned the woods. His high-set ears tipped forward slightly. His nostrils flared and quivered.

Merlin held that posture for so long, Grady began to think the dog was not so much searching for anything as he was warning away a pursuer. Yet he did not growl.