“M-maybe it’s sleeping,” Bob whispered.

Jupe shook his head. He tried to keep his voice low and calm. “Remember,” he breathed in Bob’s ear. “It’s not a real dragon.”

Bob nodded curtly. “I know. That’s what you’ve been telling us. Let’s hope you’re right.”

The boys waited another long moment. Then Jupe flicked his light on again, and ran its beam along the ground.

He smiled now, relieved.

“Look at the dragon’s feet, and tell me what you see.” Bob stared along the yellow path of light. He blinked.

“Tracks,” he said. “Right under the dragon. They look like railway tracks.”

Jupe heaved a sigh of relief.

“We were both right. The dragon’s a fake, all right. And you’ve found the underground rapid transport railway that Labron Carter built more than fifty years ago. But you were wrong about one thing, Bob. You said it had never been used!”

“What do you mean?”

“The dragon’s been using it,” Jupe replied.

“But why? I don’t get it,” Bob answered, puzzled.

Who would build a dragon to lie in an underground railway tunnel that hadn’t been used for fifty years? A railway that wasn’t going anywhere. One that would probably never be used again. It didn’t make sense.

Why? Bob wondered.

“We’re going to find out now.” Jupe was tugging at his sleeve. “Let’s go before they return.”

Bob followed Jupe slowly. “Before who returns?” Jupe didn’t answer. He kept going.

They came up to the monstrous shape huddled in the centre of the tunnel.

Jupiter frowned, puzzled.

“What’s wrong?” Bob whispered.

“I can’t figure it out,” Jupe admitted. “It’s facing the other way. Outwards, towards the beach. The fake inside wall is open, yet the outside cave entrance is still closed. What do you make of it?”

Bob shrugged. It wasn’t too often that Jupe was stumped and asked what he thought about a puzzling situation.

“It looks like whoever’s in this thing is heading out — to sea, maybe. But meanwhile they don’t want anybody coming in,” Bob said.

Jupiter nodded, his eyes bright. “I think you’ve made an excellent deduction, Bob. Let’s look over this remarkable dragon now, before it gets away from us. It could be our last chance.”

The drooping head of the dragon lay still as they circled it warily. The eyes appeared closed, lifeless. Jupe flicked his light against it briefly.

“Hmmm,” he said. “They’re not eyes at all, but small headlights! Remember how the cave lit up the last time when it entered? And how it created the illusion of blazing eyes?” Jupe chuckled. “It’s very simple. All they had to do was use lights, running lights, like a ship, or plane, or train.”

They were at the side of the still dragon now. Jupe extended his arm. His fingers seized something that gleamed oddly in the dark, scaly skin.

“Door handle,” he muttered. “That’s odd. I don’t see any door.”

Bob peered over Jupe’s shoulder. He pointed upwards. “There’s another one above it. And another above that.” Jupe laughed shortly. “Fooled me again. It’s not a door handle. These are metal ridges to put your feet on. I’m climbing up.”

Bob followed Jupe up the footholds. When Jupe was at the top of the dragon, he lifted something up and held it there. He looked down, his lips parted in amazement.

“It’s a hatch,” he whispered to Bob. “Stand guard. I’m going down to take a look.”

Bob gulped and nodded. Jupe heaved his stocky body. Then he was gone. The hatch slowly closed.

Bob started as he heard a thump inside.

It was as if the dragon had finally swallowed Jupe, Bob thought nervously.

He peered into the darkness ahead. In the light of his torch he could see the tunnel curving slightly in the distance. The tracks disappeared as the rounded wall cut off his view. The sides of the tunnel were smooth, showing ribs of steel extending to the ceiling, and patches of concrete.

He heard a rustling noise and jumped.

The hatch had opened.

“Take a look,” Jupe urged softly.

Bob clambered up quickly. As Jupe dropped below him, his feet found a narrow ladder. When he touched bottom, Jupe flashed his light round the interior.

“Neat, isn’t it? It looks like a dragon. It runs on tracks like a train. But look at this — a periscope! And this porthole. Unless I’m very much mistaken, Bob — this dragon is actually a midget submarine!”

Bob rapped the curved side wall. He rubbed his knuckles. “Whatever it’s made of, it’s pretty hard stuff.”

Jupe nodded. “It would have to be iron or steel in order to remain submerged. But I don’t think it is. Let’s see what the engine room is like.”

The boys walked forward down a narrow aisle. “Gearshift, dashboard, brakes and pedals!” Bob exclaimed. “What kind of a sub is this?”

Jupe snapped his fingers. “I remember reading of one of the first submarines ever built. It ran along the ocean floor like a car. The inventor had windows built in the sides so people could look out, and charged his passengers admission. There were special air compartments in it to withstand the water pressure.

“The dragon builder might have taken his idea from that or the Rose Bowl floats — mounted on a car chassis, covered by the roses and design of the float. They travel in low gear, directed by a driver hidden below.”

Bob snapped his fingers excitedly. “So that’s how the dragon moved along the sand without seeming to. I mean, its legs didn’t work like the dragon in the film Mr. Hitchcock showed us.”

“It’s understandable,” Jupe said. “Mr. Allen needed a more realistic type of dragon for the film he directed. The builder of this one just needed something that looks like one. Just enough to get the scare effect he wanted. Only I wish I knew why — or who he’s trying to scare.”

Suddenly an eerie sound floated through the dragon.

“Aaaaa… ooooo… oo!”

Both boys jumped.

“What was that?” Bob whispered.

Jupiter hesitated. “It came from the rear section.”

Bob looked at him. “Are you sure? I don’t want to be in this thing if it suddenly decides it wants to take a dip in the sea.”

The moaning sound came again, long, drawn-out, and chilling.

“Aaaaaaahh… ooooooo… oooo!”

Bob shivered. “I don’t like the sound of that.”

To his amazement, Jupe turned and trotted down the narrow aisle to the rear of the dragon. He stopped. The moaning sound came again. Jupe listened carefully, his head bent low to the floor.

“W-what is it?” Bob asked nervously, coming closer. Jupiter didn’t answer. He turned and directed his torch beam along the interior wall of the dragon. Then to Bob’s surprise, he smiled.

“I believe we’ve finally solved our mystery,” he said with a chuckle.

“We have?”

Bob cocked his head, listening intently. “I hear it,” he said. “I still don’t like the sound of it.”

“That’s because you’ve allowed your fear of the dragon to overcome your senses,” Jupe said, smiling. He opened a narrow door and flashed his light inside the dark opening.

The moans became louder.

Bob blinked suddenly. “Hey — wait a minute! That sounds like — ”

He craned his neck and looked inside. His jaw dropped.

“Dogs!” he exclaimed. “Whiskers! A whole cupboard full of dogs!”

“That’s the mystery solved,” Jupe said. “The mystery of the missing dogs.”

“What’s wrong with them?” Bob asked. “They look as if they’re too sleepy to move, unless they’re ill — ”

Jupiter shook his head. “Not ill. Sleepy, perhaps. My deduction is they’ve been tranquillized!”

“Tranquillized?” Bob repeated. “Why?”

Jupe shrugged. “Perhaps they got in somebody’s way. And he didn’t want to hurt them. Scientists often stun an animal with a tranquillizing dart or needle to render it harmless so they can examine it.”

One of the dogs moaned again. “Aaaaahhh… oooooo… oo!”

“That’s an Irish setter,” Bob said excitedly. “It must be Mr. Allen’s dog!”