Jeff and Mathias had wandered off across the hilltop. They were standing on the far side of it, staring down toward the clearing, talking together. Pablo had disappeared into the blue tent.

"Is there any water?" Amy asked.

Eric dug through his pack, pulled out a bottle. They took turns drinking from it.

"It's gonna be okay," he said again.

"How?" Stacy asked, hating herself for speaking. She knew she shouldn't be asking questions like that. She needed to be quiet and let Eric build this dream for them.

Eric thought for a moment, struggling. "Maybe when the sun sets, we can go back down, sneak past them in the darkness."

They drank some more water, considering this. It was too hot to think, and there was a persistent buzzing in Stacy's ears, like static, but higher-pitched. She realized she should get out of the sun, crawl into one of the tents and lie down, but she was frightened of the tents. She knew that whoever had set them up so carefully here upon the hilltop was almost certainly dead now. If Henrich was dead, then the archaeologists must be, too. Stacy couldn't see any way around this.

Eric tried again. "Or we can always just wait them out," he said. "The Greeks will come sooner or later."

"How do you know?" Amy asked.

"Pablo left them a note."

"But how can you be sure?"

"He copied the map, didn't he?"

Amy didn't say anything. Stacy sat there, wishing she'd speak again, that she'd somehow manage to clarify this question, either refute Eric's logic or accept it, but Amy remained silent, peering off across the hilltop at Jeff and Mathias. There was no way to tell, of course. Pablo might've left a note or he might not have. The only way they'd know for certain was if the Greeks were eventually to show up.

"I've never seen a dead body before," Eric said.

Amy and Stacy were silent. How could they possibly respond to a statement like that?

"You'd think something would've eaten him, wouldn't you? Come out of the jungle and-"

"Stop it," Stacy said.

"But it seems odd, doesn't it? He's been there long enough for those vines to-"

"Please, Eric."

"And where are the others? Where are the archaeologists?"

Stacy reached out and touched his knee. "Just stop, okay? Stop talking."

Jeff and Mathias were coming back toward them. Mathias was holding his hands out in front of himself, as if they were covered in paint and he was trying not to get it on his clothes. As they came closer, Stacy saw that his hands and wrists had turned a deep raw-meat red; they look scarred.

"What happened?" Eric asked.

Jeff and Mathias crouched beside them. Jeff reached for the water bottle, poured a tiny bit on Mathias's hands; then Mathias rubbed at them with his shirt, grimacing.

"There's something in the plants," Jeff said. "When he tore them off his brother, he got their sap on his hands. It's acidic. It's burned his skin."

They all peered down at Mathias's hands. Jeff handed the water back to Stacy. She took off her bandanna, started to tilt the bottle over it, thinking the wet cloth might cool her head some, but Jeff stopped her.

"Don't," he said. "We need to save it."

"Save it?" she asked. She felt stupid with the heat: she didn't know what he meant.

He nodded. "We don't have that much. We'll each need a half gallon a day, at least. That's three gallons total, every day. We'll have to figure out a way to catch the rain." He glanced up at the sky, as if searching for clouds, but there weren't any. It had rained every afternoon since they'd arrived in Mexico, and now, when they needed it, the sky was perfectly clear. "We have to get organized," Jeff said. "Now, while we're still fresh."

The others just stared at him.

"We can last without food. It's water that matters. We'll have to keep out of the sun, spend as much time as we can under the tents."

Stacy felt sick, listening to him. He was acting as if they were going to be here for some time, as if they were trapped here, and the idea filled her with panic. She had the urge to cover her ears with her hands; she wanted him to stop talking. "Can't we sneak away when it gets dark?" she asked. "Eric said we could sneak away."

Jeff shook his head. He waved across the hilltop, toward where he and Mathias had been standing. "They keep coming," he said. "More and more of them. They're all armed, and the bald one sends them out along the clearing. They're surrounding us."

"Why don't they just kill us?" Eric asked.

"I don't know. It seems like it's something to do with the hill. Once you step onto the hill, you're not allowed to step off it. Something like that. They won't step on it themselves, but now that we're on it, they won't let us leave. They'll shoot us if we try. So we have to figure out a way to survive until someone comes and finds us."

"Who?" Amy asked.

Jeff shrugged. "The Greeks, maybe-that would be quickest. Or else, when we don't come home, our parents will-"

"We're not supposed to leave for another week," Amy said.

Jeff nodded.

"And then they'd have to come searching for us."

Again, he nodded.

"So you're talking-what, a month?"

He shrugged. "Maybe."

Amy looked appalled by this. Her voice jumped a notch. "We can't live here for a month, Jeff."

"If we try to leave, they'll shoot us. That's the one thing we know for certain."

"But what will we eat? How will we-"

"Maybe the Greeks will come," Jeff said. "They could come tomorrow, for all we know."

"And then what? They'll just end up trapped here with us."

Jeff shook his head. "We'll keep someone posted at the base of the hill. To warn them away."

"But those men won't let us. They'll force them-"

Again, Jeff shook his head. "I don't think so," he said. "It wasn't until you stepped beyond the clearing that they made us climb the hill. In the beginning, they were trying to keep us away. I think they'll try to stop the Greeks from coming up, too. All we have to do is figure out a way to communicate to them, to let them know what's happened, so that they can go get help."

"Pablo," Eric said.

Jeff nodded. "If we can get him to understand, then he can warn them off."

They all turned and stared at Pablo. He'd emerged from the blue tent and was wandering around the hilltop. He seemed to be talking to himself, very softly, muttering. He had his hands in his pants pockets, his shoulders hunched. He didn't sense them watching him.

"Planes might fly over, too," Jeff said. "We can signal to them with something reflective. Or maybe pull up some of the vines, dry them out, start a fire. Three fires in a triangle-that's supposed to be a signal for help."

He stopped talking then; he didn't have any more ideas. And neither Stacy nor the others had any ideas at all, so they just sat without speaking for a stretch. In the silence, Stacy gradually became aware of a strange chirping sound-steady, insistent, barely audible. A bird, she thought, then knew immediately she was wrong. No one else seemed to notice the noise, and she was turning to track its source when Pablo started yelling. He was jumping up and down beside the mine shaft, pointing into it.

"What's he doing?" Amy asked.

Stacy watched him pressing his hand to his head, to his ear, as if he were miming talking on a phone, and she sprang to her feet, started quickly toward him. "Hurry," she said to the others, waving for them to follow. She'd realized suddenly what that steady chirping was: somehow-miraculously, inexplicably-there was a cell phone ringing at the bottom of the hole.

Amy didn't believe it. She could hear the noise coming from the hole, and-along with the others-she had to admit it sounded like a cell phone, yet even so, she had no faith in it. Jeff had told her not to pack her own phone before they left; it would be too expensive to use in Mexico. But that didn't mean there weren't local networks, of course, and why shouldn't it be possible that what they were hearing was a phone linked to one of these? It should be possible-there was no reason for it not to be possible-and Amy struggled to convince herself of this. It wasn't working, though. Inside, in her heart, she'd already dropped into a place of doom, and the plaintive beeping coming from the darkness wasn't enough to pull her free. When she peered into the hole, what she imagined was not a phone calling out to them, but a baby bird, open-beaked, begging to be fed-chirrrp…chirrrp…chirrrp-a thing of need rather than assistance.