T he pavement stopped at a variegated edge where chunks of tar met brown dust, marking the boundary between civilization and wilderness. Walt spotted Fiona’s beat-up Subaru among the vehicles parked at the Chocolate Gulch trailhead.

He was calling his location to dispatch when she knocked on the side window, startling him.

He looked at her, noticing for the first time a constellation of freckles under her jaw.

But as he rolled down the window, the freckles moved down her neck: nothing but fly specks on the glass. Some detective, he thought.

“You mind if I tag along?” she asked. “Pam wants some shots.” Pam Brummell was the publisher of the weekly newspaper, The Sun Valley Sentinel.

“No problem.” He rolled the window back up and climbed out. “It’s actually not my scene. Fish and Game.”

They walked together. At 9 A.M. the sun was quickly warming the air, the tree-covered hills alive with sunlight, the sky an indigo blue.

“I hope you’re not gloating over the fact they got the cougar before the cougar got anyone else, because that’s blind luck if you ask me.”

“For one thing,” Walt said, “I don’t gloat. For another, we have no way of knowing if this is the same cat. It’s a very dry summer. A lot of game is coming out of the hills for the river.”

“This is where the yellow Lab was killed.”

“Yes. But you and Danny Cutter and Liz Shaler were ten miles south of here. Cougars cover a lot of territory, but that’s a good hike.”

Walt admired her from behind as she mounted the trail. She walked a bit like a cat herself. They reached a backpack on the game trail and looked down through the woods to see the cat lying on her side, a man kneeling next to her. Walt and Fiona scrambled down the slope. The cat lay by a slow trickle of a stream, her black eyes open, giving the impression she was dead. But the steady rise and fall of her rib cage said otherwise. The agent had spread petroleum jelly over her open eyes to protect them from drying out, but the result was a deathly gaze.

“Sedated.” The man introduced himself as a Fish and Game agent. He looked vaguely familiar to Walt.

“She’s beautiful,” Fiona said, already preparing her equipment.

“Hell of a shot,” Walt said. “From up on the game trail?”

“Yeah. I got lucky being downwind, or she’d have bolted.”

The dart still dangled from her shoulder. There was something sad about seeing so graceful and powerful an animal brought down like this. A collision of man and nature. The pungent decay of soil and the mint of the evergreens comingled.

The agent’s dog-a yellow Lab-was tied to an aspen sapling.

Walt asked, “Is that dog trained for explosives, by any chance?”

“No, just a tracker.”

Walt thought he knew all the tracking dogs in the valley. This one was new to him.

“What’s to become of the cat?” Fiona asked, now taking photographs.

The agent pointed out the ear tag and explained she’d be caged and they’d look for a home for her.

“And if you can’t find a home for her?” she asked.

“We usually do. We have a month or more,” the agent answered.

“Doesn’t seem fair,” Fiona said. “Do we even know if she’s the one who killed the yellow Lab? I mean, is she guilty of anything?”

“We’ll be able to watch her stool for hair and bones. That’s one place caging her helps.”

“Could she possibly have been down in Starweather yesterday afternoon?” Walt asked.

“A male can travel twenty-five miles at night, while hunting. This one could have been in Hailey last night. Starweather? No problem.”

Fiona finished taking shots, packed up her bag, said goodbye to them both, and trudged back up the hill.

“It would help if we could connect this cat to the yellow Lab,” Walt told the agent. “There was an attack on a fisherman. Putting all those to bed would be a good thing.”

“We won’t be able to confirm any of that. And what I didn’t want to say was chances are we won’t find her a home.”

Walt looked down at the beautiful creature and felt depressed.

“Cougars and humans…,” the agent said, pausing, “is not a good mix. Add PCP into it, and it’s a nightmare waiting to happen. She’s trouble, Sheriff. May not be her fault, but trouble just the same.”

“Yeah,” Walt said, “but she got here first. We’re the interlopers.”

The cat’s open-eyed stare stayed with him on his return to the trailhead. Fiona’s car was gone.

He thought about finding Gail’s car parked at Brandon ’s trailer and his chest tightened. He’d spent the night on his own couch, unable to sleep in their bed. Hadn’t slept much at all. He realized his marriage had officially ended: It wasn’t just talk, and tears, and lawyers anymore, and it left an aching hole in him that even work couldn’t fill. He wanted to take the day off, maybe hike up into the Pioneers with the dogs. He wanted change, something to take away all the reminders of his own failure.

He climbed back into the Cherokee and held firmly to the wheel, unable to drive. Unable to move.

T revalian had a problem: For his plan to work he had to take possession of the second dog, a dog trained for scent-and then make a switch. The sheriff and the vet had unwittingly provided a dog to get his plan back on track. But the vet, Mark Aker, from whom he’d arranged to purchase a scent dog-a tracker-weeks ago, by phone, had been introduced to Nagler that same morning, when delivering the service dog. Trevalian felt it too great a risk to allow Aker to meet Trevalian and Nagler in the same day, for fear he might make the connection-doctors were, if anything, observant. But this was the day prearranged for him to buy the tracker, so he’d timed his arrival in the lobby of Aker’s Veteranarian Services, an expansive log structure a few miles south of Ketchum, at a time he knew Aker to be busy with an emergency surgery.

He hid his impatience from the receptionist, wandering an area crowded with parakeet cages, racks of kitty teasers, and sacks of pet food.

Then his impatience gave way and he approached the counter for the third time.

“I don’t mean to be rude but is there anyone else I might talk to about this?” he asked.

“I’m afraid he asked that you wait,” she answered.

“But the sale has been in place for several weeks,” he protested. “I’m under time constraints.”

“Mark thinks of these animals as members of the family. He handles all the sales personally.”

“But she’s ready?”

“Of course.”

“Then could I at least see her?” he asked.

“Of course you can. I’m so sorry it’s taking so long.” She came around from behind the desk and led Trevalian out of the building, across a courtyard, to a small barn. The moment they entered, a half dozen dogs started barking.

Callie was a three-year-old German shepherd with an energetic face and two black socks on the hind legs. Trevalian knelt and petted and talked to the dog.

“She’s trained to track, yes?” he asked the receptionist.

“All the Search and Rescue dogs are,” she replied. “All are expert trackers. Yes.”

Trevalian asked for a demonstration, and the receptionist humored him. He watched and listened carefully to the specific commands used. He committed them to memory, along with Callie’s expressions and reactions. She gave him two full demonstrations-the dog obviously enjoying the game of pursuing a scent and receiving a reward for her success.

Trevalian glanced at his watch, making sure the receptionist saw him do so. “Certainly it can’t make any difference who takes my cashier’s check.”

“Mark would kill me. We’ve spent over a year training Callie. He’s going to want to say goodbye.”

Trevalian considered killing her himself.

“And if he loses a twenty-thousand-dollar sale?” Trevalian proposed.