"Of course," Devon cautioned, "we don't know for sure that's where Tommy is."

But I knew in my gut that it was. All that stuff about spirits and dreams, and visiting other worlds . . . it fit too well. Something strange was going on, and this place was at the center of it.

I felt a flutter of excitement in the pit of my stomach. Like you feel when you are about to step off a high diving board for the first time. Fear and elation all tangled up together.

"You're going to go there," Rita said. Not a question.

I didn't respond.

"Whatever's going on there probably won't be aboveground," she warned. "And we can hardly just wander in the main entrance without being noticed."

"They built a new entrance in 1936," Devon reminded her. "That means that somewhere there may be an old one that's still accessible. If we can locate that . . ." He turned back to the computer and started typing again.

"You two don't have to go," I said quietly. "He's not your brother."

"Hey." Rita glared at me. "This isn't just about your brother, okay? Devon and I are on the same hit list you are. So are a lot of our friends. So on the off chance there's something out there that will tell us what's going on-and why-I sure as h.e.l.l want to be there when you find it."

Devon nodded as he typed. "This may take a while, Jesse. Why don't you go take a shower, get changed . . ." The words trailed off as he focused on the computer.

Get ready to leave this place of safety. Get ready to invade dark places where dangerous people-dangerous creatures-might reside.

I started to protest, but then stopped myself. There was nothing I could do in this living room right now that would make our situation any better, and meanwhile, I wanted to get clean so badly I could taste it. So I went and collected the clothes they'd left out for me, and a fluffy white guest towel, and headed off to the bathroom to wash off the mixture of soot and sweat and fear that clung to my skin. A lot of fear.

The latter didn't wash away completely, but I tried my best.

Night was falling; the woods surrounding us were dim, like a photo that had faded over time. A breeze stirred my newly washed hair, scattering droplets of water across the shoulders of my camo T-shirt. Yeah, camo: the kind of thing you wear when you want to hide out in the woods. That tells you something about what those two were thinking when they shopped for me.

Prescient of them.

Devon came out onto the narrow deck and joined me at the railing.

"Find anything useful?" I asked.

"An old map. Won't know how accurate it is until we get there. I cached a satellite image of the local terrain."

I hesitated. "Do your parents know we're here?"

"My dad knows I'm here. He thinks I'm off hiking this week, using the cabin as a base of operations. Hopefully we'll be back before he realizes that isn't the case. My mother . . ." He paused. "She died a few years ago."

"I'm so sorry."

He shrugged stiffly. "Beltway collision. Still hard to accept." He offered me the phone. "You want to try your mom?"

I hesitated. I did want to talk to my mother, more than anything in the world. She must have been going crazy not knowing where I was. But the mere thought of taking the phone from him made my hand start shaking, as the full implications of our situation hit home: Whoever wanted to kill me must surely have realized by now that the fire had failed, and they'd be looking for me, to try again. If they were smart they'd be watching my mother's every move, possibly even tapping her phone. The one sure way to find me.

I might have been willing to take a chance with my own life, but they'd proven they were willing to kill my family to get to me, and I didn't want to put her in danger.

I'm sorry, Mom. I blinked back tears as I waved off Devon's offer. I'm sorry I can't tell you that I'm okay. I know it must be tearing you to pieces inside, not to know what happened to me.

"Hey," he said gently. "It's okay. We'll be back soon enough. Maybe with enough solid evidence to give to the police. That's the goal, right?"

"And what if something goes wrong along the way?" I whispered. "What if we don't come back? No one will ever know what happened to us."

He nodded, and I got the sense that this was something he'd already considered. "We can leave a note in the cabin. If I don't check in for a few days my dad will start to worry, and eventually he'll come out here and find it. That'll give us enough time to check out the caverns without interference, but also guarantee that we get backup eventually, in case anything goes wrong."

I nodded dully. It wasn't a perfect plan, but it was the best we were likely to come up with.

"You could leave a letter for your mother," he offered. "I'm sure my dad would deliver it."

"Thanks," I whispered.

He hesitated, then put his hand over mine. It felt strong and certain and it vibrated with positive energy. I tried to draw strength from it.

"C'mon," he said. "We need to head out to Front Royal while the Walmart is still open."

In my letter, I told Mom everything. Never mind how crazy some of it sounded when you put it in writing; if she got this letter it would mean that the worst had happened, in which case she had to know it all. I even drew her a picture of Tommy's kidnapper. I tried to make him look realistic, but he still came out looking like a s.p.a.ce alien in a hoodie. My hand shook as I drew Tommy's small body draped over his shoulder.

I hope you never have to read this, I thought, as I sealed my letter and put it beside Devon's. I hope we come back soon enough that no one even knows we were gone.

Rita didn't leave a letter for anyone.

9.

FRONT ROYAL.

VIRGINIA.

RITA'S CAR WAS A SLEEK BLACK AUDI, which was not what I'd expected. Turned out it wasn't her car after all. I figured that out when we stopped in a bad neighborhood in Front Royal so she could leave it on the street with the key in the ignition. She wiped the steering wheel down carefully first, then the door handles and gear shift, removing her fingerprints with a thoroughness that suggested she'd done that kind of thing before. Maybe her prints were "in the system."

She caught my eye as she slid into the back seat of Devon's SUV, apparently reading some kind of challenge in my expression. "I was worried about you that night," she said defiantly. "I wanted to see if anyone was casing your house. What was I supposed to do, walk?"

I muttered something that I hoped was appropriate. I honestly didn't know what to say to someone who would steal a car just to take a trip across town, though I was certainly grateful she'd done it.

The trip to Walmart was apparently so we could stock up on bottled water. And backpacks to put the water in. And flashlights. And rope. And chalk. And three of those folding utility knives that have all sorts of household tools tucked into them.

"Are you expecting to get lost in a cavern?" I asked Devon, trying to keep my tone light.

"No one ever expects to get lost in a cavern," he pointed out reasonably.

He told us that if there was anything Rita and I thought we should pack, that he'd left out, we should go get it. So I headed over to the hardware department, because, as every fan of Mythbusters knows, the single most important thing to have with you in unfamiliar territory is duct tape. Rita disappeared into Housewares and soon returned with three large kitchen knives. They were the kind you see in horror movies, when the heroine is being hunted by a killer inside her own house, and she searches in the kitchen drawer for the deadliest looking weapon she can find. They were long and triangular and surely would scare off the most hardened serial killer.

We also picked up a set of children's walkie-talkies (Devon's idea), pocket-sized first aid kits (my idea), and a box of breakfast bars (Rita's idea). We bought everything in threes, which was actually kind of disturbing, as it meant we were planning to get separated. That was a possibility I was trying hard not to think about.

Devon's parents had given him a credit card for emergencies, but he'd intentionally left it at the cabin, not wanting to risk it getting into the hands of the wrong people. That left him only with the cash he'd withdrawn from his personal bank account when we'd arrived in Front Royal. After all our stuff was paid for, there wasn't much left. Hopefully, whatever emergencies lay ahead wouldn't be expensive ones.

It was dark by the time we finally pulled back onto Route 340, heading south. Rita sat in the back seat, trying to cut up the clamsh.e.l.l packaging from her kitchen knives so that we could use them as sheathes. I munched on a breakfast bar without tasting it, trying not to think about what kind of creatures might be waiting for us just down the road.

They're human beings, I told myself stubbornly. The one that took Tommy was probably wearing some kind of disguise, to fool security cameras.

But try as I might, I couldn't get those alien eyes out of my head.

Devon was using the car's GPS to navigate, and after about half an hour it directed him to turn left, onto a narrow dirt road. Soon after that he killed the lights, which made the last part of the drive somewhat harrowing; tree branches seemed to jump out of nowhere, and giant potholes were all but invisible until you were right on top of them. Once we bottomed out so hard I feared the axle might get broken. My nerves hadn't been all that calm to start with, and this wasn't helping.

Finally he stopped and parked. We were in the middle of nowhere.

"I don't see a cave," Rita said.

Devon nodded. "I don't want to bring the car too close to it, they might hear us coming. We can walk from here."

Even with our flashlights, visibility was poor. The ground was rocky and uneven and the trees looming overhead blocked most of the moonlight. More than once I stubbed my toe on some unseen obstacle, or heard Rita curse as she did the same. Devon had brought his smartphone along, complete with a GPS app and some cavern maps that he'd cached, so at least there was no chance of us getting lost. But it was one h.e.l.l of a walk.

Finally the ground leveled out and the trees gave way to a plain of tall wild gra.s.s. Devon glanced at his device again and nodded; by unspoken agreement, we all turned off our flashlights. We were getting close to something and couldn't take the risk that we might be seen.

Silently we skirted the gra.s.sy area, moving as quietly as we could manage. Then we came over a rise and saw what must once have been the Mystic Caverns tourist center. A semi-circle of small buildings flanked one large one at the center, all of them designed to look like log cabins. Whatever signs might once have identified them were missing, and the buildings were so weathered and aged that the whole place looked like a ghost town. But the surrounding gra.s.s had been neatly mowed, and near the main building there were tire tracks plainly visible. My heart skipped a beat when I saw them. Had the vehicle that made those brought my brother here?

We skirted the compound with care, which, as it turned out, was a really good idea, because someone had strung up barbed wire around the place. It was nearly invisible in the moonlight, and Devon almost walked right into it. Whoever owned this place really didn't want visitors. Which, when you were searching for kidnappers and arsonists who were trying to kill you, was a pretty good sign you were in the right place.

When we got to the far side of the compound we could see that there were several vehicles parked behind the main building, including a small shuttle van. But the compound was silent, and there wasn't any light visible in or around the buildings; whoever owned those vehicles was probably underground.

As we moved past the entrance the trees closed in on us again, and Devon checked his GPS app. "That way," he whispered, pointing southwest. We moved as quietly as we could in the thick underbrush. I kept looking behind me as I walked, straining to see if we were being followed. Thus far, it seemed, we were un.o.bserved.

Then Devon whispered "There!" and pointed to something directly ahead of us.

In the dim moonlight I could make out a small cabin, its weathered planks green with mildew. At one time, the surrounding land must have been cleared, because there were no large trees near it, though dozens of smaller ones had sprouted up, and a thick carpet of tangled brush covered the ground. I was willing to bet that no one had come here in a long time. If we were lucky, the new owners didn't even know this place existed.

The cabin had no door, just a simple rectangular archway like you might find at the opening of a mine. Someone had nailed wooden planks across it, and while the job wasn't neat, it was thorough; there were enough nails in the wood to keep a recycling center busy for a week.

"Jeez," Devon muttered. "I didn't think to bring a crowbar." He considered the problem for a moment, then took his utility knife out of his backpack and began prying loose fibers of wood from the edge of one of the planks. Rita and I couldn't help him without getting in his way, so we stood watch. Finally, when he had made a hole big enough to fit his hand into, he grasped the upper edge of the plank, braced his foot against the door frame, and pulled. At first the plank didn't budge, and it looked like we would have to figure out some other way to break inside. But then suddenly it gave way, and fragments of moldy wood went flying in every direction as he jerked the plank away from the archway and threw it into the brush.

Now there was room for all three of us to grab the next plank down, and we made short work of it. Two more gave way after that, until we had an opening large enough for a person to climb through.

Pausing to catch our breath-dismantling an eighty-year-old shack is surprisingly hard work-we shined our flashlights into the small building, to see what was there.

The interior was empty, and most of the floor was just flattened dirt. But near the rear of the building the ground looked darker, and when we swung our flashlights that way we could see the opening of a deep black pit. Inside, it looked like there might be some kind of staircase leading down. Devon's research had come through for us.

I stared at the hole for a moment, and my hand trembled, making the beam from my flashlight jerk around a bit. The reality of what we were doing-and the sheer danger of it-was sinking in. If anyone other than Tommy had been kidnapped by aliens, I might have turned around and headed home right then and there. Only for family did you do something like this.

But we can't go home, I reminded myself. I could see in my companions' eyes that the same thought was running through their heads. If we returned home now, without answers, we'd just be putting our families at risk. No one was going to investigate this place for us based on the kind of evidence we currently had, so we'd wind up sitting at home helplessly, just waiting for someone to come kill us.

Better to take our chances with the unknown.

Deciding that since this was my venture I really should go first, I started to climb inside, working my way gingerly over the remaining planks. But the rotting wood gave way beneath me and sent me crashing to the ground inside the cabin. I fell full length, which mean that my head wound up less than a foot from the gaping pit. For a moment I just lay frozen, fear surging through my veins, while tendrils of cool air from the netherworld chilled the sweat on my skin.

"Are you okay?" Devon asked.

"Yeah," I muttered. "I think so."

Slowly, carefully, I edged myself away from the pit. It took me a minute to catch my breath and to still the wild beating of my heart; then I crawled over to where my flashlight had fallen and retrieved it. Devon and Rita were climbing through the entrance-more carefully than I had done-and by the time I was back on my feet, they were standing beside me.

Now we had a better angle on the pit and could shine our lights straight down into it. There was indeed a flight of stairs, carved out of the bedrock itself. The steps were narrow, steep, and uneven, and it went without saying there was no handrail. They went down as far as our light could reach and then were swallowed up by the darkness of the pit. Nameless malevolence seemed to waft up from the depths.

"Just when you need an elevator the most," Devon muttered.

"Should have picked one up at Walmart," Rita chided him.

"Next time," he promised.

The banter steadied my nerves a bit. I felt ready for this. Taking a deep breath, I started to descend into the earth. It wasn't easy. The treads weren't wide enough to accommodate my feet in a normal walking position; I had to turn them sideways and work my way down the staircase like a crab. The stairs were damp, too, which meant they were slippery. I tried to find handholds on the rock wall to steady myself, but there were very few, and the descent was pretty scary. Flashlight beams played about my feet as Rita and Devon descended behind me, balancing precariously on stairs that had not felt the weight of a human foot for eight decades. If either of them slipped, we'd all go down.

But I finally reached the bottom, and moments later the two of them joined me. As I waited for them I swung my flashlight beam around the long, narrow cavern that we were now standing in. The nearer end appeared to have been hewn from the rock by some sort of hand tool; deep gouges criss-crossed the wall in parallel groupings, as if a giant cat had sharpened its claws there. A few yards beyond that the s.p.a.ce opened up into a natural chamber, the kind they call a "live cave," whose walls were slick with moisture from recent rains. There were small calcite icicles hanging down from the ceiling, and ripples of glistening stone seemed to be have been frozen in place as they trickled from cracks in the walls. This place had been famous in its time, I recalled, and with caverns like Luray and Skyline right down the road, that meant it must have some pretty impressive formations.

There was only one direction to go in, so we started walking, following a path of rough bricks half-covered in mud. The original tourist route? Running along one wall I saw a horizontal ridge that looked man-made, no doubt disguising an electrical line. There were probably lights down here somewhere, disguised as cave formations so as not to distract tourists. But even if we found functional lights, and they were still hooked up to a power source, we could hardly risk turning them on.

Devon turned his phone off as we walked, to conserve its power. Our flashlights provided some light, but not nearly enough to drive back the oppressive cave darkness. As we walked, their narrow beams made the formations flanking our path look like stuff out of a horror movie. Spires would suddenly appear overhead, from nowhere; waterfall-shaped cascades of limestone seemed to shift position as we pa.s.sed by, and curtains of translucent calcite rippled like jellyfish. My parents had taken me to visit Luray Caverns back when I was a kid, and I remembered how beautiful such formations could be, when viewed in the proper lighting. But when viewed this way they were unsettling, and we were all acutely aware of how many hiding places there were in the darkness surrounding us, that might shelter any manner of enemy or trap.

But thus far, no one seemed to know we were there.

Suddenly I thought I heard something other than our footsteps, and I motioned for everyone to stop moving. Straining my ears, I could just barely make out a sound in the distance.

I looked at my companions to see if they had heard it too. They both nodded. Someone else-or something else-was down here.

Rita and Devon switched off their flashlights, and I kept mine pointed downward as much as possible; it barely gave us enough light to walk safely, but we had to minimize the chance that anyone ahead would see us coming. Periodically we stopped to listen again; each time the distant sound seemed louder. It was beginning to sound like human speech, though the echo from the caverns made it hard to pick out individual words. We seemed to be heading right toward it, and I wondered if we would really be so lucky as to have our path lead straight to the kidnappers we sought.

But then we came to a place were the line of bricks turned off to the right, while the voices were coming from the left. There seemed to be no way to continue walking in the direction we needed to go. Anxiously, we searched the left wall of the chamber for any kind of pa.s.sage, and Devon finally found a narrow crevice hidden in the shadows. Little more than a crack in the wall, it looked like something no man in his right mind would enter; but then I saw the thin line of concrete running down one of its walls, and realized it must have been used as a maintenance tunnel. Good enough.

One by one we squeezed ourselves into the narrow s.p.a.ce. Devon went last, and before he committed himself to the crevice he took out a piece of chalk and marked the ceiling overhead. Always the organized one. Rita had her knife in her hand again. I wondered what it would feel like to stab someone. I wondered, if circ.u.mstances called for it, if I would be able to. I wondered if Rita ever had done so.

The floor of the pa.s.sageway was covered with a thick layer of mud, and our feet made soft squelching sounds as we worked our way through the narrow s.p.a.ce. Way too conspicuous for my taste, but there was no helping it. Sometimes the ceiling dropped so low that Devon couldn't get through without crouching, and at one point the pa.s.sage grew so narrow that I had to slip off my backpack to squeeze through it sideways. Meanwhile the light was growing brighter by the moment, so we knew we were headed in the right direction. The voices were gone, though; even when we stopped our mud-squelching to listen for them, we could hear nothing.