She gritted her teeth, and forced her dress back on, the fabric rolling and twisting uncooperatively as she wiggled. For one moment, her foot slipped on the rock. She teetered precariously, looking down at the oozing mud. She dropped down on the rock and held on tight.

Her heart hammered against her ribs. Oh, she wanted done with this. She wanted to go home. She wanted to see her mother. She wanted a wonderful Minnesotan winter, when she could run outside and fling herself into the deep white snow. She remembered how the flakes tasted on the tip of her tongue. The sensation of fresh ice crystals melting in her mouth. The delicate tickle of more flakes feathering across her eyelashes.

Was she crying now? It was so hard to know with all the sweat on her face and the flies encrusting the corners of her eyes.

“I love you, Ma,” Tina whispered. And then she had to break off the thought before she definitely wept.

She looped her bra around the jug handle, fastened it around her purse and pushed it behind herself. The dragging weight of it was awkward, and the water sloshed up dangerously close to the uncapped top, but it was the best she could do. She had her supplies. Next.

She balanced on the rock, then grimly fell forward against the wall. Her hands scraped against the surface, catching her weight. Then she searched for vines. She found six. She wrapped three around each hand, feeling them bite into her sunburned hands. Time to grin and bear it.

Tina stepped out of her highly impractical shoes. One last deep breath. The sun beating down on her head. The sweat rolling down her cheeks. The bugs buzzing, buzzing, buzzing.

Tina pulled on the vines with both arms while simultaneously throwing her right foot at the wall. Her toes scrabbled for traction against the algae-slick surface, found a drier patch and dug in. On the count of three, she heaved up with her arms.

And simultaneously felt the vines give way. She was falling back, her leg already kicking back, trying to find her rocky perch. The water gallon jug swung wildly, further upsetting her balance. She wasn’t going to make it, she was going to fall into the stinking muck.

Tina pushed desperately with her hands, releasing her panicked grip on the vines. She went careening back onto her rock. Windmilling, twisting, then suddenly, gratefully, collapsing down onto the stable surface. The water, water, water. Her hands frantically found the jug, still magically upright and holding the last of her precious supply.

She was back on her rock, she had some water, she was safe.

The vines collapsed into the muck below. As they did so, she noticed their edges. Cut clean halfway through. And then came the fluttering piece of white paper, as if loosened by the turbulence above.

Tina reached up a tired hand and felt the paper fall into her palm.

She drew it toward her.

It read: HEAT KILLS.

“You son of a bitch,” Tina tried to scream, but her throat was too dry, the words coming out as a mere whisper. She licked her lips. It did no good. She hung her head tiredly, and felt the last of her strength leach from her body.

She needed more food. She needed more water. She needed a break from this desperate heat if she was ever going to survive. And now the bugs were back, the mosquitoes, the yellow flies, feasting, feasting, feasting.

“I’m not going to die here,” she muttered resolutely, trying to summon some force of will. “Dammit, I won’t do it.”

But if she couldn’t make it up out of the pit…

Very slowly, Tina’s gaze went to the thick, slithering muck.

Shenandoah National Park, Virginia

4:25 P . M .

Temperature: 99 degrees

“THE SEARCH AREA HAS BEEN DIVIDED into ten different sections. Each team of two should analyze their section on the map, then work it in the standard grid pattern. In the good news department, since the hiker has been missing for only twenty-four hours, she shouldn’t have wandered beyond a thirty-mile radius, giving us a fairly contained target for search. In the bad news department, this thirty-mile radius contains some of the harshest, steepest terrain in the entire park. Here’s what you need to know:

“One, lost hikers inevitably head down. They’re tired, they’re fatigued and once they lose their sense of direction, they’ll head down the mountain even when help lies just twenty feet away over the next hill. Two, hikers will also gravitate toward the sound of running water. Everyone knows how important water is, especially someone who is disoriented. If there is water in your section of the grid, check the areas around the streams carefully and follow them for as long as you can. Three, once off the groomed hiking trails, this is rough country. The underbrush is thick, the footing treacherous. Be on the lookout for upturned rocks, broken branches, and trampled underbrush. If this woman is still on the trails, chances are someone would’ve seen her by now. So most likely she’s in the wild and we’re going to have to do this the hard way.”

Kathy Levine paused for a moment, gazing out somberly over the group of twenty search-and-rescue volunteers now gathered at Big Meadows Lodge. “It’s hot out, people. Yeah, no kidding, you’re thinking. But I mean it. In this kind of heat index, dehydration is a constant threat. The rule of thumb is that two quarts of water a day keeps dehydration away. Unfortunately, in these conditions your body can easily lose a quart of water per hour through your lungs and pores, so two quarts isn’t going to cut it. Frankly, each person should carry two gallons of water, but since that weight would be prohibitive, we’re requiring each rescue team to carry either water tablets or a water purification system. Then you can refill your water supply at the various streams you encounter along the way. Don’t drink untreated stream water. Sure, the water looks clear and pretty up here, but most of it is contaminated by Giardia lamblia-a parasite which is guaranteed to give you a bad case of the seven-day trots. Drink often, but drink smart.

“Now, assuming that you stay properly hydrated, don’t slip down a steep hillside, or stumble upon a sleeping bear, there are a few final things to keep in mind. For example, rattlesnakes. We have plenty. Every now and then, you’ll come to a clear meadow with a pile of rocks from an old landslide. Looks like a terrific place to sit down. Don’t. The snakes think so, too, and most of those rocks are their homes. Let’s not argue with them. Second, we have hornets. They like to build nests in old hollows in the ground or in rotten logs. If you leave them alone, they’ll leave you alone. If you step into a nest, however… might I recommend not running back to your partner. You’ll only drag him into the mess and one of you will need to be able to hike back for help. Finally, we have stinging nettles. If you haven’t ever seen one, they are about thigh-high with broad green leaves. If you boil them, they actually make a pretty good green to go with dinner. Walk into them, however, and welcome to nature’s version of fiberglass. The prickers get immediately under the skin and emit a poison that remains long after the thistles are gone. It takes a good thirty to sixty minutes for the inflammation to subside and by then, you’ll have renounced everything you once held dear.

“This park is beautiful. I’ve walked almost every inch of it in the last five years and I can’t think of a more beautiful spot on earth. But nature also commands respect. We need to be focused. We need to move fast. But in these conditions, I also need each and every one of you to always be using your head. Our goal is to find one person, not lose any more. Any questions?” Levine paused. There were none. “Good,” she said crisply. “Let’s move. We have only four and a half hours of daylight left.”