Tensely, the Hardy boys crouched in the tunnel, as they heard the voice of the Dodds’ former hired man.

“It’s a dirty night out,” he was saying. “You’re welcome to the trip, Dan.”

“Still raining?”

“Pouring. I’m soaked to the skin,” grumbled Montrose. “It’s no fun, ploughing down through that gully.”

“Well, you won’t have much more to do tonight,” said one of the men placatingly. “We landed a fine roadster while you were out.”

“The one I was telling you about?”

“The same.”

“Seems funny about that car being parked on the Shore Road three nights in a row. I saw it there the other evening and passed it up. Then last night I got in and would have driven it away, only I couldn’t get it started. Different kind of car than any I’ve ever been in. I went out and found Sam and we were going back when we ran right into the car turning around in a lane.”

“Didn’t see who was in it, did you?”

“No. The headlights shone right in our eyes. Seemed like a couple of young fellows. If they had been a little slower we’d have had the car.”

“Well, we have it now. They’ll wish they wasn’t so smart, leavin’ it out in the rain that way.”

“Nice wet walk they’ll have if they live in Bayport,” laughed Gus Montrose shortly. “I know who I wish owned it.”

“Your little friends?”

“Those brats of Hardy boys,” returned Gus. “Followed me for about three blocks today when I went uptown to meet Sam.”

“What was the big idea?”

“Aw, they kid themselves that they’re a couple of amateur detectives,” rasped Montrose. “Just because they’ve been lucky in a couple of cases they think they gotta go spyin’ on everybody.”

“What made ’em spy on you?”

“How should I know? I guess Dodd must have put them up to it.”

“They don’t figger you’re mixed up with these missin’ cars, do they?”

“How could they? Nobody has anythin’ on me,” bragged Gus. “But I told them a few things, anyway. I told ’em to lay off followin’ me or they’d get somethin’ they wasn’t lookin’ for.”

“What’d they say?”

“They backed down. Got scared and beat it.”

“That’s the way to talk to them,” approved the man called Dan. “Scare the daylights out of them.”

“Speakin’ of daylight⁠—it’ll be daylight before you reach Atlantic City with that car if you don’t hurry up.”

“All right. All right. I’ll start movin’,” Dan growled.

“You might as well take some of that junk we got from the Importing Company’s truck, and ask Clancy to sell it for us. And don’t you forget to collect the money from him for the last car we turned over to him.”

“I won’t forget. Some of you guys had better come along and load a couple of those boxes for me.”

There was a heavy tramping of feet, that indicated the men were leaving the cave. The Hardy boys could hear their receding footsteps and the diminishing voices. Finally the cave was in silence.

Frank peeped out of the tunnel.

“They’ve gone,” he whispered.

“Are you going in?” questioned Joe.

“Sure. There’s no one around.”

He stepped out onto the rocky floor, with Joe at his heels.

The cave was not as large as the one in which the cars were stored, but from the boxes scattered around and from a litter of empty cigarette packages, burnt matches, old clothes, and other things lying about, it was clearly the meeting place of the gang.

“Well, we’ve found the auto thieves, all right. The next thing is to trap them.”

“We can’t do it alone, that’s certain,” said Joe. “I think we ought to get out of here as quickly as we can.”

“There’s probably only one opening to this place,” answered Frank, flashing the light about the walls.

It fell on a dark opening through which the thieves had departed. There was no other passage apparent, beyond the one through which the boys had entered.

“Not much use going after them. They’re probably all out in the cave where the cars are kept,” remarked Joe.

“We’ll just have to watch our chance.”

“Let’s take a look around here,” remarked Frank, after a minute of silence.

“We’ll have to be careful. They may come back and catch us,” answered his brother.

“We’ll watch out for that.”

With caution the boys began to look around them.

“Look!” cried Frank in a low tone.

He bent down and from the rocky floor picked up a big bunch of keys.

“Auto keys,” came from Joe.

“Yes, and all different. I suppose they have all the keys necessary to unlock any car.”

“More than likely.”

Near the keys they found a dark coat and a cap.

“I guess the keys dropped out of that coat,” remarked Frank.

“Looks like it.” Joe’s gaze traveled to a spot back of the coat. “Look, a wig!” he exclaimed.

“That shows they go out disguised.”

“It sure does. Say, we’re getting to the bottom of this mystery!”

“I hope so.”

The boys explored the underground chamber, but found nothing of further interest.

“So we were right, after all,” Frank said. “Gus Montrose is mixed up with the auto thieves.”

“He probably discovered these caves in the first place, and saw how they could be used for concealing stolen goods. Perhaps this place was used by smugglers long ago.”

“Probably. They are natural caves, and it’s easily seen that they’ve been used for a long time. Some of the tunnels look as if they’d been blasted out to widen them. We’re certainly lucky to have found their hiding place, for we’d never have found it unless we’d been brought here.”

“From their talk, they evidently drive the cars to Atlantic City from here.”

“Must have a secret road of some kind, or they’d never get through.”

“Montrose spoke of coming through a gully.”

“There is a gully near the Dodd farm. Now that I come to think of it, I believe there is an abandoned road through it. The place has been overgrown with brush for the past five years, though.”

“Perhaps they cleared it out.”

“The road used to lead out to one of the private, right-of-way roads in the back township. Since the Shore Road was extended, it’s never been used. I’ll bet that’s what they’re doing⁠—using that old road and bringing the cars out the back way. The police haven’t been watching the private roads at all.”

“It’s a smart scheme. Well, it won’t last much longer.”

Suddenly, a voice rang out, clear and sharp:

“I’ll get the lantern. It’s right here.”

Startled, the boys wheeled about. The voice seemed to be right beside them. Instantly, they realized that it was only a trick of the echoes, and that the voice came from the passage leading into the cave.

Someone was approaching. They could hear his heavy boots clumping on the rocky floor.

“Quick! The tunnel!” whispered Frank.

He sped across the cave toward the opening in the wall. But they had moved farther away from their hiding place than they imagined. By the time the brothers reached the passage, they heard a cry of alarm behind them.

“Who’s that?”

They scrambled into the tunnel.

Another shout, footsteps across the floor, and then the lantern cast its beam directly on the entrance of the passage. It was a powerful light and the boys knew they had been seen.

The man in the cave began shouting for help:

“Gus! Sam! Come here! Quick!”

His voice echoed from the walls.

The Hardy boys heard a faint shout from outside the cave.

“What’s the matter?”

“Someone in here. Hurry up!”

The uproar out in the cave grew in volume as other members of the gang joined their comrade. There was a hasty gabble of voices.

“There was someone in the cave when I came back for the light,” shouted the man who had discovered the boys. “They beat it into that tunnel. I just saw them.”

“Sam, go around and watch the other side!” ordered someone sharply. “That tunnel goes out into the big cave.”

The thieves were evidently unaware of the cave-in that had blocked the passage. Frank and Joe retreated beyond the first bend. They were trapped. The barricade cut off their flight, and they knew they were facing certain capture.

“The guns!” snapped Frank.

He drew his revolver from his pocket and fired into the darkness, around the corner.

There was a shout of alarm.

“Get back! Get back, Gus! They’ve got guns!”

Then followed a wild scrambling, as the man who had pursued them into the tunnel hustled back to safety.

Frank pressed himself against the rocky wall, in case any of the gang should enter and open fire on them. But the thieves had been frightened by his shot.

“That’ll hold them for a while!”

“How long?” Joe reminded him. “They have us trapped, Frank. We can’t go back. They’ll starve us out.”

“We won’t give up without a fight.”

There was a tremendous uproar out in the cave. The men were talking loudly and their voices were intensified by the tumultuous echoes of the place.

“Follow them in!” someone shouted. But Gus snarled:

“We can’t. They’re armed.”

“Well,” said Frank quietly, “we have enough bullets to keep them back for a while, at any rate.”

“They’ll get us, in the long run.”

“I suppose so.”

Then the Hardy boys heard the voice of the man called Sam. He came into the cave, shouting:

“They can’t get out! There’s been a cave-in and the tunnel is jammed up with rock.”

“Good!” exclaimed Gus exultantly. “Here! Hand me that light.”

There was a moment of silence. Then the powerful lantern was evidently turned toward the mouth of the tunnel, for the light gleamed on the walls. As they were just around the bend in the passage, the boys could not be seen, but the glaring light was reflected from the rocks.

“They’re out of sight,” muttered someone. “Try a shot!”

Instantly, there was an explosion, as a revolver roared. The echoes were deafening in that confined space.

Something whizzed past Frank’s head and smacked against the rock.

The bullet, aimed for the rock wall, had ricochetted across the bend and had missed him by a hairbreadth.

This was too close for comfort. The revolver crashed again, and there was a cry from Joe.

“Are you hurt?” asked Frank anxiously.

“No. But the bullet glanced off the rocks. I think it went through my sleeve. It sure was close.”

Their voices had been heard by the men in the cave.

“That’s got ’em scared!” yelled Gus.

The boys retreated out of range of the glancing bullets.

“We’re up against it,” Frank admitted. “If we stay here they’ll starve us out. If we try to rush them, we’ll get shot.”

“I guess we’ll have to surrender.”

“Looks as if there’s nothing else for it. We’ll give ourselves up and take our chances on escape. The way things are, we’re liable to be shot.”

He edged back toward the bend in the passage. There was a lull in the firing.

“We give up!” he shouted.

A yell of triumph followed.

“Now you’re talkin’ sense!” shouted Gus. “Throw your gun out here.”

Frank hurled his revolver around the corner and it clattered on the rocks. Someone crawled into the passage and retrieved it.

“Now come out with your hands up.”

Bitter though their defeat was, the Hardy boys had to acknowledge that the odds were against them. With their arms in the air, they came around the corner, into the glare of the big lamp. Step by step, they advanced until, at the junction of cave and tunnel, they were seized by their captors.