Henry opened all the drawers of the bedroom dresser. Then he checked his suitcase, which was also in the middle of the bedroom. “That’s strange. Nothing’s missing—not money, not our camera. Hey, wait! Where’s my headlamp? I’m pretty sure I left it right on the dresser.”

  The children checked the whole cabin. Henry’s headlamp was nowhere to be found.

  Henry shrugged. “As far as I can tell, somebody moved all our luggage from the closet. Unless I left my headlamp in Grandfather’s car, I think somebody took it. The question is, why would anybody want it?”

  “I don’t know,” Jessie said, “but I’m double locking this door right now.”

  Everyone decided it was too late to figure anything out tonight and got ready for bed. Benny crawled under his covers and said to Henry, “I’m sleeping with my suitcase right under this bed.” But before Henry could say anything, Benny had drifted off to sleep.

  CHAPTER 3

  An Underground Monster

  By eight o’clock the next morning, nearly every table in the Dragon’s Mouth Coffee Shop was filled. The Aldens stowed their backpacks and rock hunting tools under the last empty table. They could hardly wait for breakfast.

  Mr. Howe soon arrived to take their orders. “ ’Morning, Aldens. I recommend the flapjacks. The cook happens to be a good friend of mine—been married to her for forty years. Meantime, let me fill you up with orange juice.”

  “We’re going rock hunting today, and I’m going to find a Rockville ‘diamond,’ ” Benny announced. “See, here’s a picture of one in my rock book.”

  Mr. Howe took a look at Benny’s book. “Hmm. I’ve got a Rockville ‘diamond’ on display right behind the cash register. You can go get it, young fella.”

  Benny dashed off and returned a few seconds later with a crystal-clear rock chunk. It looked amazingly like a huge diamond.

  “You should lock this up,” Benny said with excitement. “What if it’s a real diamond, not just a crystal? It could be worth zillions of dollars.”

  “Then I’d be a zillionaire and have to retire to a golf course. That wouldn’t be nearly as much fun as running my motor court and coffee shop, would it?”

  “Nope, I guess not,” Benny answered. He turned the clear rock crystal every which way to catch the light. “Look, Jessie. It’s like the one in my book.”

  “It sure is,” Jessie agreed. “Now we’ll know what to look for.”

  While they waited for their flapjacks, the Aldens passed around the Rockville diamond before Benny put it back.

  “Those flapjacks will last you awhile,” Mr. Howe said later when the Aldens came over to pay the check. “Now let me get a look at your rock hunting gear. I can lend you some of my own tools, if you’d like. Rock collecting’s one of my hobbies when I’m not here or at the registration desk.”

  Henry opened up a canvas duffel bag. “We have a real geologist’s hammer, plus some chisels, a guidebook to the best areas, some gloves, brushes, and a strainer.”

  Mr. Howe checked the Aldens’ equipment carefully. “Good. I see some safety goggles in here, too. Don’t forget to put them on when you’re hammering rock. You don’t want a rock splinter in your eye. As for this guidebook, you won’t be needing that. I’ll let you folks in on a secret. Hike all the way to the top of Little Nose Cliff then down the other side. Some interesting rocks at the bottom were uncovered when it was blasted to make room for a road over there. I just bought a hundred acres on that side, so it’s okay by me if you chisel there. If you hammer long enough, you might find some of our Rockville diamonds buried in the rock.”

  “Hey, thanks, Mr. Howe,” Henry said.

  The Aldens were nearly out the door when Mr. Howe gave them one last piece of advice. “There’s a big meadow at the bottom of the cliff. Good place to have lunch. Just watch out for any sinkholes in the ground. I haven’t had a chance to really explore any of the sinkholes since I bought the property. But some of them go down into caves. So watch where you step. Don’t worry though, there are so many ways out of the caves it is almost impossible to get lost.”

  “Good thing I packed our lights and candles,” Jessie said on the walk back to Little Nose Cliff. “We’ll be ready in case we do find a cave. I just wish we had Henry’s headlamp.”

  Henry sighed. “Me too. Maybe a hiker thought the cabin was open for anybody and took the headlamp. Since nothing else is missing, I didn’t want to worry Mr. Howe about it in case it’s in Grandfather’s car. Well, I’m not going to let it spoil our rock hunting. Let’s have a good time.”

  Forgetting Henry’s headlamp, the Boxcar Children made their way up Little Nose Cliff past their cabin. Up and up they went, careful to watch every step so they wouldn’t slip or send rocks tumbling down.

  “Look at this view!” Henry said when everyone got to the top.

  Violet looked down at the motor court far below. “The cabins and cars seem like dollhouses and toy cars from way up here.” They headed down the other side.

  “Neat rocks,” Jessie said when the children got to the bottom of the cliff. “The colors and surfaces are different on this side of the cliff.” She dug into the duffel bag for Benny’s rock book and flipped the pages until she found what she was looking for. “I think this is the kind of rock that’s supposed to have the Rockville diamonds in it.”

  Benny touched the rock. “I don’t see any diamonds. Just plain old rock!”

  Henry put on a pair of goggles and handed another pair to Benny. “They don’t just fall in your lap, Benny. We have to dig for them inside the rock.”

  The children took turns sharing the goggles and the hammer. They chipped and chipped at different sections of rock. Two hours later, they still hadn’t found anything that looked like the famous Rockville diamonds.

  After a while, Jessie noticed that Benny wasn’t having much fun. “I know it seems as if we just ate breakfast, but it’s almost lunchtime. I’m hungry from our long hike. How about you, Benny?”

  Benny took off his safety goggles and licked his lips. “I’m hungry for our ham sandwiches. And something cold to drink, too. All this hammering makes me thirsty.”

  Everyone collected their equipment and searched for a picnic spot away from the road.

  “Let’s try the meadow Mr. Howe mentioned,” Jessie said. “We can come back to this rock later.”

  “This meadow is pretty, but I wish we could put our blanket down in some shade,” Violet said. “How about by that tree and some bushes over there?”

  Violet led everyone to a cool spot near some rocks and a shady tree. Jessie and Henry spread out the blanket. Then they laid out the food and poured ice-cold lemonade into their cups.

  Benny gulped his lemonade and sandwich, then put down the cracked pink cup he brought everywhere with him. “That tasted good,” he said, ready to explore again. “Hey, guess what? There’s cool air coming from this hole in the ground—whoops—”

  “Benny!” Violet cried out.

  The other three children ran over to where Benny had been standing. He was gone!

  “Benny! Benny!” Henry yelled. “Where are you?”

  “Down here, here, here,” the children heard Benny’s voice echo from somewhere below. “Fell in, fell in, fell in.”

  “It’s a sinkhole into a cave!” Henry said when he looked down. “Benny’s right here. Jessie, run back and get our flashlights and some rope.”

  “I’m okay, okay, okay,” Benny said, not sounding a bit worried. “It’s just a little ways down.”

  “Hang on, Benny,” Henry yelled into the hole. “Here we come.”

  When Jessie came back with the rope and flashlights, she sat at the edge of the sinkhole, then lowered herself down with no problem. Benny was there, holding his penlight to see better.

  “Isn’t it neat down here?” Benny asked, grinning. “Wait till you see the rest.”

  “Shh, here comes Violet.” Jessie stood to the side so Violet would have plenty of space to climb down.


  “I’m glad you’re safe, Benny,” Violet said. “I was afraid this hole went way way down, and we’d never find you again.”

  “Well, here I am,” Benny said, just as if he were standing in Grandfather’s backyard.

  Since Henry was so tall, he came down with no trouble at all. Then he turned on his flashlight to get a better look at the cave.

  “It slopes down then turns into a long tunnel,” Jessie said, going a bit ahead of the others. “I wonder if anyone knows about this cave.”

  “I think so!” Benny cried out. “Look! There are footprints in the dirt. See?”

  The children beamed all their lights to where Benny was pointing. Indeed, deep footprints led down toward the end of the cave.

  Benny was really excited now. “Can I go ahead a little bit, Jessie? Can I? Please?”

  Jessie gave a nod. “Okay, but just a few feet,” she said. “First let me tie this rope around your waist. We don’t want you to disappear again.”

  The others beamed their lights so Benny could see where he was going, which wasn’t too far. He sounded brave, but he didn’t want to disappear either. Staying within the light beams, Benny took a few steps down the tunnel. He was just a few feet in front of Jessie when he suddenly ran back and nearly slipped on the muddy floor.

  “A monster!” Benny yelled. “There’s a monster in this cave!” His voice was shaking now. “I saw giant footprints and something like a big tail print right behind them. It must be the dragon!”

  “Let me look,” Jessie said. Beaming her flashlight on the muddy floor, Jessie saw what Benny had reported: huge footprints, followed by a pointed, flat track. Something awfully big—maybe a giant tail—had been dragging on the ground!

  With each step, Jessie took a deep breath. There had to be an explanation.

  “Did you see the monster tracks?” Benny asked when Jessie returned.

  Jessie swallowed hard before she answered. “I saw tracks, but they could be anything.”

  “Anything with a lot of feet and one big tail!” Benny said.

  “Come on, let’s talk about this outside,” Henry suggested.

  The children went back to the sinkhole entrance. But before they could climb out of the cave, two giant feet came through the sinkhole.

  “What?” Jessie said in a hoarse whisper.

  The feet were followed by legs, then the whole body of a man who was even taller than Henry.

  “Who’s down here?” a man’s voice boomed as he pulled a large burlap sack down behind him.

  The Boxcar Children nearly froze to the cave floor.

  Henry stepped forward to greet the man. “Hello, we’re the Aldens. We’re exploring down here.”

  The man flashed his own flashlight to get a better look at the children. “Who?”

  “The Aldens,” Jessie said in a firm voice. “We were rock hunting nearby on Mr. Howe’s property. He told us we could. Then we found this cave by accident and decided to look around. What’s your name?”

  The man didn’t answer. He turned away from the Aldens and headed to the sinkhole entrance.

  Benny was right behind. “I’m Benny Alden. Do you have your lunch inside that big bag? We have a bag, too, but it’s on our picnic blanket. Were you going to have your lunch down here because it’s so hot outside?”

  The man snorted but didn’t answer Benny’s question.

  “I guess I’ll call you Joe Caveman,” Benny said.

  Whether he liked this name or not, Joe Caveman wasn’t about to become friends with the Aldens. He whirled around, heaved his bag up, then boosted himself up from the sinkhole.

  “Why was Joe Caveman in such a hurry to get out of here when he saw us?” Violet asked.

  “I don’t know,” Henry answered.

  “And I wanted to ask him if he’s ever seen the monster,” Benny sighed.

  “Maybe he’s our monster,” Jessie said.

  CHAPTER 4

  A Mysterious Visitor

  The next day, the Aldens didn’t want to waste a minute. They were going back to the “monster” cave. They had a quick breakfast of cold cereal and milk instead of going to Dragon’s Mouth Coffee Shop.

  “Today we wear our oldest jeans and tops,” Jessie told her brothers and sister. “And boots. It’s muddy in that cave. You never know when you might come across an underground stream.”

  “Or even a lake,” Henry said. “Let’s see. I think I’ve got everything—ropes, flashlights, candles, a roll of reflective tape, and a first-aid kit, too. It’s a perfect caving day—no rain in the weather forecast, so we won’t have to worry about flooding.”

  Jessie helped Violet and Benny zip up their backpacks. “While Henry and I finish packing, you two run down to Mr. Howe. Tell him where we’re going and when we’ll be back. Careful cavers always do that before they set out.”

  “Do careful cavers always bring food along, too?” Benny asked.

  “Of course,” Jessie said, “so don’t worry about that.”

  By the time Violet and Benny reached the coffee shop, it was nearly empty. Mr. Howe was at the register ringing up Nelly Stoner’s bill.

  “Jessie said to tell you we’re going caving,” Benny announced.

  Mrs. Stoner smiled at the two children. “Are you now? And what cave are you going to?”

  Violet looked up at Mrs. Stoner. “A cave that—”

  “Has a monster in it!” Benny cried out before Violet could answer. “A monster with big feet and a tail and everything. I found a sinkhole to a cave. It has monster tracks in it.”

  Mrs. Stoner’s eyebrows shot up. “Whoa, slow down, Benny. You don’t mean the dragon monster? Why, that’s only the name of one of the shapes in the big cavern. We do have a few live critters in our caves, but they’re small—salamanders, bats, and such. Occasionally some other animals wander in.”

  “A man wandered into the cave we were in,” Violet explained. “But he wouldn’t tell us his name.”

  “I called him Joe Caveman,” Benny said. “He wouldn’t tell us what was in his big sack, either.”

  Mr. Howe scratched his chin. “Hmm. Could be any number of local spelunkers.”

  “Lunkers?” Benny asked. “What are those?”

  “I’m a spelunker,” Mrs. Stoner said. “And so is Mr. Howe and a lot of other folks around here. Spelunkers are people who explore caves. That’s their hobby. I bet your Joe Caveman is a spelunker. His sack was probably full of caving supplies,”

  “But what about the monster tracks?” Violet asked. “Henry and Jessie saw them, too.”

  Mr. Howe shook his head, smiling. “Well, you children will just have to become spelunkers and find out all about that monster. I’ll want a full report. In the meantime, I have an important job for you when you visit your cave.”

  “What is it?” Benny asked in an excited voice. “We like important jobs.”

  Mr. Howe leaned on the counter. “Here’s what you do. Get a stick a few feet long and tie a handkerchief at the top. Then poke it in the ground right by the sinkhole entrance before you go down again.”

  “I know why!” Violet cried. “If we’re gone too long, someone can find us. But don’t worry, Mr. Howe. Henry and Jessie won’t let us get lost.”

  “I’m sure they won’t,” Mrs. Stoner said as she left the coffee shop with the children. “I know you Aldens will have fun. The caves around here don’t go too far, so you’ll be just fine. Besides, I know from your Aunt Jane that you children know how to take care of yourselves no matter where you go. Good luck.”

  The Aldens had plenty of good luck. After coming down Little Nose Cliff they spotted the sinkhole with no trouble at all. This time Benny didn’t fall in.

  “There!” Benny said when they reached the entrance. He poked a long stick in the ground.

  Violet tied a purple bandana to Benny’s marker. “It looks just like a flag in case anyone wants to find us.”

  Henry held up a roll of silver tape. “We won’t be needing a rescue with thi
s. We’re going to stick pieces of this reflective tape on the walls as we go in. Then we’ll follow them when we come out. It’s simple.”

  “You forgot something,” Benny said before Henry could say anything else.

  “What’s that?” Henry asked.

  “Good cavers always bring plenty of food and water,” Benny answered.

  Henry handed everyone their backpacks. “Good thinking, Benny. Ready? Put your hats on now so we don’t get drips in our eyes.”

  One by one, the Aldens threw their packs down the sinkhole then lowered themselves into the cave. Today, the four heavy-duty flashlights they carried made it easy to see that the cave stretched out quite a ways.

  The Aldens were careful. At every turn, Henry put up a small piece of tape to mark the place.

  Benny aimed his flashlight at the cave floor. “There are those monster tracks again! Can we follow them, Jessie?”

  Jessie turned around. “Not just yet. Since this is our first time in this cave, we’d better not go off on a wild goose chase.”

  “I wonder if we’ll see Joe Caveman today,” Benny said after the children began walking.

  Violet shivered. “I wish we would see some other cavers. It’s so quiet down here. There could be a storm outside or even a truck driving over where we’re standing, but we wouldn’t know it.”

  Step by step, Jessie led the group deeper into the cave. Suddenly she stopped so fast, Benny bumped smack into her. “Wait!” she whispered. “I hear a clinking sound. And there’s a speck of light up ahead, too.”

  Henry squeezed by to get a look. “Shh. Let’s turn off our flashlights for a minute.”

  Except for the light in the distance, the cave was pitch-black. The children felt their way along the walls with their hands. Everyone took small steps so they wouldn’t slip or bump into each other. Finally, they got close enough to see where the bright light was coming from.

  Benny tapped Jessie on the shoulder. “Is it Joe Caveman?”

  “No, it’s a woman,” Jessie whispered. “She’s wearing a hard hat. She just put down something. Should we say anything, Henry? I don’t want to scare her.”