“It took me a minute to see it,” Zander said once we’d all scrambled up into the damp little cave. “At first I thought the back wall was solid. See? It’s so dark that you can’t see what’s that corner.” We looked where he was gesturing and saw that he was right. One corner of the cave was nothing but blackness, far enough back that not even the tiny bit of sunlight filtering through the waterfall reached its depths. Pucci, who seemed nervous, hopped along the floor of the cave, looking for light.
“But when I crawled back there, I couldn’t find the wall, so I started feeling around and… look.” All of a sudden, Zander was gone.
I pushed the button on my vest that turned on the solar light. M.K. did the same. The lights illuminated a huge tunnel ahead of us, stretching away deep into the rock and rising high above our heads.
Zander was standing there, grinning at us, his arms spread out to show us the tunnel.
“Could this be it, Kit?” Sukey asked. “I thought it was going to be a canyon.”
“I did, too,” I said. I started to take the map out to look at it, but before I could, we heard, through the rushing of the water, a cacophony of clanking and shouting and we all ducked back into the little cave, peeking out into the blinding sunshine to see a phalanx of IronSteeds approaching the falls. The big metal horses stopped and Leo Nackley, after a bit of waving and gesturing, used a pair of binoculars to survey the falls. We quickly ducked back into the darkness.
“They’re here. What are we going to do?” Sukey asked. For the first time since I’d met her, she actually seemed scared and I realized that all of Lazlo’s talk about BNDL must have gotten to her.
I wanted to make her feel better, so I said, “Remember that they didn’t see the map that we saw. As far as they know, there’s absolutely nothing special about the waterfall. They’re just looking for us.”
“You’re right. So what do we do?” She sounded relieved.
“We get as far away from them as we can and we find the secret canyon,” Zander said. “Come on.”
Zander, M.K., and I switched our lights on again, and the four of us, Pucci riding on Zander’s shoulder, stepped into the tunnel. It was completely dark—the lights illuminated only small splashes of rock in front of our feet—and we walked for ten minutes or so before Sukey said, “I don’t see any canyon. This just looks like some kind of cavern.”
I got the map out of the inside pocket of my vest and looked at it again. “I assumed it was a canyon,” I said, embarrassed, “and Raleigh said Dad was looking for one. . . But I guess it could be an underground tunnel, or a series of underground caverns. There are a lot of those in this area. Geologically, it’s a fascinating—”
“You guess?” Sukey cut me off. “I thought you were good at reading maps.”
“He is good at reading maps,” M.K. said.
“Well, see these contour lines here?” I pointed my light at the map and showed her the thin lines marking the depth of the tunnel. “The map doesn’t show whether or not there’s a ceiling. In a sense, this is a canyon, an underground one that formed in the center of the rock.”
Sukey looked skeptical. “The legend doesn’t say anything about the treasure being in a tunnel, does it?” she asked.
“Come on,” Zander said. “It’s on Dad’s map. Whatever it is, let’s see where it goes.”
We started walking, Sukey in the middle since she didn’t have a light, Pucci hopping along anxiously, inspecting the walls.
“Did someone make this?” M.K. asked from somewhere behind me. Her voice echoed strangely in the tunnel, bouncing off the walls and along the passageway.
“I don’t think so. I’d have to feel the walls, but they look smooth. It must have been formed naturally, probably by acidic water that dissolved the limestone or by an underground river.”
I stopped and touched the stone wall, snatching my hand back when I felt something wet move under my fingers.
Sukey must have felt it, too, because she gasped. “There’s something there,” she said. “Something on the wall. I just felt it move.” Standing still now, we became aware of strange noises coming from the walls of the tunnel, faint sucking, whispering sounds that echoed back and forth across the passage.
Zander swung around and shone his light on the curved wall. At first it just looked like some kind of luminescent stone, the surface a glowing green color. But when I looked closer, I saw that the entire surface of the stone was moving. “They’re slugs,” he whispered. “But…” We all crowded around to look, and sure enough, I could see that the wall was covered with giant green slugs moving slowly across the rock and making the weird sounds we’d heard. Zander took a knife out of his pack and knocked one off the wall and onto the ground. It was the size of a small banana, its moist green skin almost translucent. When Zander pointed his vest light at the slug, it twitched, shrinking as though the light bothered it.
“Yuck,” Sukey said.
But Zander wasn’t disgusted at all. “This is incredible! I think we’ve discovered a new species. I’ve heard of giant slugs in the Amazon and Fazia and Australia, but I didn’t know they could be found in the American Southwest. I think they must be photosensitive. They must live all their life cycle in this cavern. This is amazing! I need to take a specimen.” He rooted through his vest and found a small bag, but there was no way the giant slug was going to fit in it. He stared at it for a moment without saying anything, then put the bag away.
“That’s an excellent question.” He knocked another off onto the floor and inspected the wall where it had been. “Moss,” he finally announced triumphantly. “There’s some kind of luminescent moss growing there.”
“Does he always get this excited about slugs?” Sukey asked.
“He wants to be an explorer-naturalist,” I told her. “He wants to discover a new species.”
“I just did,” Zander said. “The Zander West slug.”
Pucci went over and pecked halfheartedly at the slimy length of it.
“Too big for you, Pucci, huh?” M.K. patted his head. “Zander, what kind of animal could eat these slugs?”
“I don’t know.” In the light from my vest, Zander suddenly looked nervous. “Let’s keep going.”