“There may be another pocket or passage inside,” Bob suggested, “That could warm it, too, Jupe.”

Jupiter shook his head, his mouth forming the stubborn line they were accustomed to seeing when he disagreed with them.

He took out his pocket knife and started to scrape at the rough grey slab.

Pete laughed. “You’ll only ruin your blade trying to cut through that rock, Jupe. What you need is a small stick of dynamite.”

Jupiter ignored Pete’s remark and continued scraping away at the wall surfaces. He looked at his blade and saw lumpy grey particles clinging to it.

He turned to face his companions. His mouth was open with a triumphant smile as if he had something important to reveal. But as he looked over their shoulders, his smile faded.

“The cave,” he said hoarsely. “I d-don’t know how but it’s opening behind you!”

His companions whirled in disbelief. There had been no opening before. How could it be opening now?

They watched, with staring eyes, what had to be impossible!

The cave opened wider, slowly. It became somewhat lighter. They felt a breeze.

They stood staring, their hearts pounding wildly, as it continued to open. They could dimly see the sand now, and farther out, the darker line of the ocean.

Jupiter was the first to speak.

“Quick! We’ve got to get back into that smaller cave!”

The Three Investigators ran forward and threw themselves at the small rock that had opened for them before.

Bob pressed at it frantically with his hands. He hit it with his shoulder. Then he looked at his companions, his voice shaking.

“I–I forgot how I did it before. I can’t open it!”

“Impossible,” Jupe grunted. “It was just a matter of leverage. We can find the spot.”

He joined Pete in pressing and pounding the resisting rock, while Bob continued his own search for the pressure point he had found earlier.

Light suddenly flooded the cavern, and they froze. The cave opening was widening. And something was moving towards them. Something huge and dark from the sea!

Pete gripped Jupe’s shoulder. “Am I seeing things?” he gasped.

Jupiter, stunned, shook his head. His mouth was very dry and his eyes blinked rapidly. “No — ” Jupe replied hoarsely “ — it’s a dragon, all right!”

The monstrous serpentine shape came closer and they could see water glistening on its dark wet skin. The shadowy head was small and triangular, held high on a long, swaying curved neck. Its yellow eyes were fixed on the cave, and bored into them like twin headlights. It advanced, making a strange humming sound.

In another moment, it was close enough to block the cave opening. Its head dipped low and the boys saw its long forked tongue flick in and out, as if getting ready to taste them. It hissed. Its hum was like a longing sigh.

Frantically, they continued their efforts to escape from the cave, hitting and throwing their weight against the rock from every possible angle.

“A-a-a-agh!” The monster was entering the cave now and they could hear its rasping breath.

They cringed back against the rock as the terrifying dragon loomed high above them. Then the long curving neck swung round and the dark head with its great staring yellow eyes lowered.

The long wet jaws opened and they saw its teeth, incredibly large and shining. It breathed again in its harsh rasping manner, and then it coughed and stopped.

Jupiter had read of the warning cough of the great jungle tiger as it prowled for prey. But he had never thought much about it. He remembered it now and shuddered.

His eyes were riveted on the dark head of the monster. It swayed back and forth hypnotically. Then, suddenly, it dipped closer towards them. Jupiter shrank back against his companions, his hands still frantically searching for the trigger point of the stubborn, unyielding rock behind him.

The dragon’s wet jaws loomed closer. Now they opened again and the frightened boys felt its hot steaming breath.

Suddenly the rock behind them clicked and trembled. Jupiter turned as it opened and saw Bob fall through. Pete sat frozen, staring helplessly up at the dragon. Jupiter jerked his arm and shoved him through after Bob. Then, holding his breath, he hurled himself through the narrow opening.

The rock rumbled shut, and the boys sighed their relief. But it was short-lived.

They heard the muffled, angry roar of the dragon. Then they felt the rock tremble as something heavy clawed and pounded at it from the other side.

“It’s coming after us!” Pete cried.

The roaring noise from the other passage grew louder. The rock that linked the two caves trembled under the pounding. Sand and small rocks started to fall from the roof of the small cave they were huddled in. The air became clouded with dry, gritty dust.

“Landslide!” Pete said, coughing.

“We’re trapped!” Bob cried. “We’ll suffocate!”

Jupiter remembered what they had been told about the cave—the danger of landslides, of being buried alive.

It appeared Arthur Shelby had not been joking.

More rocks fell. The pounding and roaring seemed to grow in intensity. Jupe shook his head, trying to get rid of his helpless creeping terror.

Dazed and frightened, he found his eyes fixed on the planks at the other end of their cave. Of course! It was incredible how fear fogged one’s mind. “The planks!” he yelled. “We go out the same way we got in!”

The three frightened investigators leaped for the boards. Jupe and Bob scooped desperately at the loose sand at the bottom, while Pete stood pounding at the thick board, trying to move it. In another moment that seemed like a lifetime, it was free. They squirmed through.

They swung the big board back and hastily kicked sand underneath it, wedging it in place. Then they looked at each other, panting.

Jupe’s head bobbed.

“Now we run for it!” he said.

Jupiter didn’t intend to lead the way. His feet did it for him. They took him straight out of the mouth of the cave. Then he was on the sand, running.

Right beside him was Pete. Pete was the best athlete of the trio, and the fastest runner. Bob was next. Ordinarily neither of them would have had any trouble passing Jupiter.

Their torches made erratic bobbing paths of light as they ran. They passed the broken staircase. Finally, they were at the steps of the second staircase that ran to the top of the ridge. Worthington was up there, they knew, and the powerful Rolls-Royce that could whisk them to safety. Behind them was the roaring creature that had come out of the sea, and was angrily looking for them.

They were halfway up and still there was nothing behind to snatch at them with cruel jaws and hot steaming breath. Then they were on the top, panting and gasping for breath.

Ahead of them, far in the distance, were the twinkling lights of Los Angeles. And parked down the street, was the waiting car with Worthington at the wheel.

They raced to the big, sleek Rolls-Royce, its metal parts and golden door handles gleaming in the moonlight. The door was flung open, and they piled into the rear seat.

“Worthington!” Jupiter panted. “Take us home.”

“Very good, Master Jones,” the tall, dignified chauffeur replied, and the big car came purring to life. It picked up speed and began its long sweeping turn down to the Pacific Coast Highway, going faster and faster.

“I didn’t know you could run so fast, Jupe,” gasped Pete.

“Neither did I,” Jupe replied through puffed cheeks. “Maybe — it’s because — I never saw — a dragon before.”

“Whiskers!” Bob exclaimed, as he leaned back against the leather-cushioned seat. “Am I glad we’ve got the use of this car!”

“That goes double for me,” Pete said. “But how do you figure that dragon showing up, after we had decided there couldn’t be any such thing?”