They were animal footprints. A coyote, thought Maura, or perhaps a wolf. Although blowing snow had obscured the prints in places, it was obvious that they moved in a direct line toward their house.

“It must have left these prints last night,” said Grace. “Or maybe the night before. Because they’re all frozen over now.” She turned toward the woods. “And there’s something else I want to show you.”

Grace headed across the field, following the tracks toward a snow-covered mound. It was just a white hillock, its features blending into the vast landscape of snow, where everything was white, where bush and boulder were indistinguishable beneath their thick winter blankets. Only as they drew closer to the mound did Maura see the streak of yellow peeking through, where Grace had swiped away the snow to reveal what was underneath.

A bulldozer.

“It’s just sitting out here in the open,” said Grace. “Like they were in the middle of digging up something and they just… stopped.”

Maura pulled open the door and looked into the driver’s cab. There was no key in the ignition. If they could somehow get it started, they might be able to plow their way up to the road. She looked at Grace. “You wouldn’t know how to hot-wire an engine, would you?”

“If we had Google, we could look it up.”

“If we had Google, we’d be long gone from this place.” With a sigh, Maura swung the door shut.

“See these tracks?” said Grace. “They go right past here and head toward the woods.”

“We’re in the wild. You’d expect to find animal tracks.”

“It knows we’re here.” Grace looked around uneasily. “It’s been sniffing around us.”

“Then we’ll just stay inside at night, okay?” Maura gave her arm a reassuring squeeze. It felt so thin, so fragile through the jacket sleeve, a reminder that this girl was, after all, only thirteen. A child with neither her mother nor her father to comfort her. “I promise, I’ll fight off any wolf that comes to the door,” said Maura.

“There can’t be just one wolf,” Grace pointed out. “They’re pack animals. If they all attacked, you couldn’t fight them off.”

“Grace, don’t worry about it. Wolves rarely attack people. They’re probably more scared of us.”

The girl didn’t look convinced. To prove she wasn’t afraid, Maura followed the tracks toward the trees, into snow that was deeper, so deep that she suddenly plunged in over her knees. This was why deer so easily fell prey in the winter: Heavy animals sank deeply into the snow, and could not outrun the lighter and nimbler wolves.

“I didn’t do it, you know!” Grace called out after her. “I didn’t take her stupid purse. Like I’d even want it.”

Suddenly Maura spotted a new set of impressions, and she paused at the edge of the trees, staring. These prints had not been left by wolves. When she realized what she was looking at, a sudden chill lifted the hairs on the back of her neck.

Snowshoes.

“What would I want with her purse, anyway?” said Grace, still standing by the bulldozer. “You believe me, don’t you? At least you treat me like a grown-up.”

Maura peered into the woods, straining to make out what lurked in the shelter of those pines. But the trees were too dense, and all she saw were drooping branches and tangled underbrush, a curtain so thick that any number of eyes could be watching her at that moment, and she would not be able to see them.

“Elaine acts all sweet and concerned about me, but that’s only when Dad’s around,” Grace said. “She makes me want to barf.”

Slowly, Maura backed away from the woods. Every step seemed alarmingly loud and clumsy. Her boots cracked through the snow crust and snapped dead twigs. And behind her, Grace continued.

“She’s only nice to me because of him. Women always start off being nice to me. Then they can’t wait to get rid of me.”

“Let’s go back to the house, Grace,” Maura said quietly.

“It’s just an act, and Dad’s too blind to see it.” Grace paused as she suddenly saw Maura’s face. “What’s the matter?”

“Nothing.” Maura took the girl’s arm. “It’s getting cold. Let’s go inside.”

“Are you pissed at me, or what?”

“No, Grace, I’m not.”

“Then why are you squeezing me so hard?”

Maura instantly released the girl’s arm. “I think we should get in before it’s dark. Before the wolves come back.”

“But you just said they don’t attack people.”

“I promised your dad I’d look after you, and that’s what I’m trying to do.” She managed a smile. “Come on, I’ll make us some hot chocolate.”

Maura did not want to make the girl any more fearful than she already was. So she said nothing to Grace about what she had just seen in the woods. Elaine, though, would have to be told. They needed to be prepared, now that she knew the truth.

They were not alone in this valley.

IF SOMEONE’S OUT THERE, WHY HAVEN’T WE SEEN HIM?” ASKED Elaine.

They sat awake late in the night, alert to every creak, every rustle. On the sofa, Grace slept deeply, unaware of their tense whispers, their anxious speculation. When Maura barred the door and propped a chair against it, Grace had assumed it was to keep out the wolves. But tonight it wasn’t four-legged predators that Maura and Elaine were afraid of.

“The prints are recent,” said Maura. “Any older than a day or two, and the wind and blowing snow would have covered them.”

“Why haven’t we seen any other prints?”

“Maybe he’s managed to erase them. Or he’s watching us from a distance.”

“Which means he doesn’t want us to know he’s out there.”

Maura nodded. “It would mean that.”

Elaine shivered and looked at the hearth. “Well, he’d certainly know we’re here. He could probably spot our light from a mile away.”

Maura glanced at the window, at the darkness outside. “He could be watching us now.”

“You could be all wrong. Maybe it wasn’t a snowshoe.”

“It was, Elaine.”

“Well, I wasn’t there to see it.” She gave a sudden, hysteria-tinged laugh. “It’s like you’re making up some crazy campfire story, just to freak me out.”

“I wouldn’t do that.”

“She would.” Elaine pointed at Grace, who slept on, unaware. “And she’d get a kick out of it. Was this her idea, to play a practical joke on me? Because I don’t think it’s very funny.”

“I told you, she doesn’t know about it. I didn’t want to scare her.”

“If there is someone out there, why doesn’t he just come up and introduce himself? Why’s he hiding out in the woods?” Her eyes narrowed. “You know, Maura, we’re all going a little crazy out here. Arlo’s seeing ghosts. I can’t find my purse. You’re not immune. Maybe your eyes are playing tricks on you, and those weren’t snowshoe tracks. There’s no watcher in the woods.”

“Someone else is in this valley. Someone who’s known about us since we arrived.”

“You only found those tracks today.”

“There’s something else I haven’t told you about. It happened the first night we got here.” Maura glanced at Grace again, to confirm that the girl was still asleep. She lowered her voice to a whisper. “I woke up in the middle of the night and there was snow scattered on the floor. And a footprint. Obviously, someone opened the door, letting in the wind. But all of you were sound asleep. So who opened that door, Elaine? Who came into this house?”

“You never mentioned this before. Why are you only telling me about it now?”

“At the time, I assumed that one of you had stepped outside during the night. By the next morning, the footprint was gone, and there was no evidence left. I thought maybe I’d dreamed the whole thing.”

“You probably did. You’ve built up this paranoid fantasy over nothing. And now you’re freaking me out because of some footprint you thought you saw in the woods.”

“I’m telling you this because we both need to be alert. We need to watch for other signs.”