Half an hour later he sighted the black, shadowy cliffs and cruised slowly in toward them.
He didn’t see the dome until the tank was almost on top of it. Then he cried out in amazement, jerked the tank to a halt and flattened his face against the glass, playing the spotlight on the ruins of the dome.
Old Gus’ dome had been literally blown to bits. Only a few jagged stumps of its foundation, firmly anchored to the rock beneath, still stood. The rest was hurled in shattered fragments over The Bottom!
There was no sign of Old Gus. Apparently the old man had been away when the dome had crashed or his body had been carried away.
But there was little mystery as to what had caused the dome to fall. The broad wheel marks of a large undersea tank led away from the scene of destruction. Deep footprints still made a tracery about the dome site and the interior of the dome had plainly been rifled after the dome itself had been destroyed. This had been the work of men. A shell, loaded with high explosive, driven by compressed air, had smashed the dome.
“Robber’s Deep,” said Grant, half to himself, staring along the direction in which the tank trail led. The tale of Robber’s Deep, as he had heard it from Old Gus, had sounded like one of those tall tales for which The Bottom men were famous. Tales inspired by superstition, by loneliness, by the strange things that they saw. But maybe Robber’s Deep wasn’t just a tale—maybe there really was something to it after all.
Grant turned back to his waiting tank. “By Heaven,” he said, “I’m going to find out!”
The tread marks were easy to follow. They led straight away, down the slope toward the Big Deep, then angled sharply to the north, still leading down.
The water grew darker, became a dirty gray with all the blue gone from it. Sparks flittered in the darkness—flashes that came and went, betraying the presence of little luminous things—sea life carrying their own lanterns. Arrow worms slid across the vision plate, like white threads. Copepods, the insects of the deep, jerked along with oarlike strokes, like motes of dust dancing in the sunlight. A shrimp, startled, turned into a miniature firecracker, hurling out luminous fluid which seemed to explode almost in Grant’s face.
A swarm of fish with cheek and lateral lights flashed by the glass and a nightmare of a thing, with flame-encircled eyes, bobbing lantern barbells and silver tinsel on its body, crawled over the nose of the tank, perched there for a moment like a squatting ogre, then slipped out of sight.
The gauges were swinging over. Deeper and deeper, with the pressure rising. The grayness of the water held and the lights outside increased, like little fireflies rustling through the gloom.
What had happened to Old Gus? And why had his dome been smashed?
Those two questions pounded in Grant’s brain. If Gus was still alive, where was he? Out rounding up the vigilantes he had spoken of? Hurrying back to Deep End to inform the police? Or haunting the trail of the marauders?
Grant shrugged his shoulders. Old Gus probably was dead. The old coot was depth-dippy. He would fight at the drop of the hat, no matter what the odds. Somewhere a blasted tank or a shattered suit was hidden in the ocean’s mud, marking the last resting place of the old Bottom man.
But why the attack on the dome? Could Old Gus have had treasure there? It was not unlikely. He had talked of old ships loaded with treasure, he was watching a five-foot clam with a pearl as big as a man’s hat. Even at the lower price of pearls due to their greater abundance now, that pearl itself would represent a small-sized fortune.
The trail led deeper and deeper, down into a darker gray, with more fireflies dancing, with monstrous shadows slipping through the water. Weird formations began to thrust themselves out of the ocean bed and the trail dipped swiftly. The track of the larger tank wound tortuously around the outcroppings.
Without a doubt they were approaching Robber’s Deep. The depth gauge read slightly under two thousand feet and the pressure gauge sent a shiver of fear along Grant’s spine. Exposed to that pressure for an instant, a man would be jelly—less than jelly, less than a grease spot on the floor.
The trail led into a narrow canyon, with mighty rock walls rearing up straight into the water. There was barely clearance for Grant’s tank—the larger machine must have almost brushed the walls.
Suddenly the canyon debouched into a wider space, a sort of circular arena, with the walls sweeping to left and right and then closing in again narrower than ever, forming a little pocket.
Grant jerked the machine to a stop, tried frantically to spin it and retreat. For in that little arena were other tanks, a battery of them, large and small.
He had run slam-bang into a trap and as he ripped savagely at the controls he felt the cold perspiration trickling down his chest and arms.
A voice boomed in his radio receiver: “Stay where you are or we’ll blast you!”
He saw the snouts of guns mounted on the tanks swiveling around to menace him. He was beaten and he knew it. He halted the tank, switched off the motor.
“Get into your suit and get out,” boomed the voice in the receiver.
He was in for it now—clear up to his neck.
Out of the tank, he walked slowly across the arena floor. A man from one of the tanks came out to meet him. Neither of them spoke until they were face to face.
Then, in the dim light, Grant recognized the man in the other suit. It was the Rat!
“Nice hide-out you have here, Rat,” said Grant.
The Rat leered at him. “Hellion will be glad to see you,” he said. “This is a sort of unexpected visit, but he’ll be glad to see you just the same.” The Rat’s face twisted. “He liked your message.”
“Yes,” said Grant, “I figured that he would.”
Alcatraz on Ganymede had done something to Hellion Smith, had instilled in him a deeper, sharper cruelty, a keener cunning, a fouler bitterness. It showed in his squinted eyes, his twitching face with the jagged scar that ran from chin to temple, the thin, bloodless lips.
“Yes,” he told Grant, “I have a nice place here. Convenient in a good many ways. The police would never think to hunt for me down here and if they did and we wanted to make a fight of it, we could hold them off until the crack of doom. Or if we wanted to run for it, they’d never be able to trail us through those canyons that run into the Big Deep.”
“Clever,” said Grant. “But you always were clever. Your only trouble was that you took a lot of chances.”
“I am not taking them any more,” said Hellion, but his tone still held that puzzling, light note of pleasant conversation.
“By the way,” he said, “the Rat told me you remembered me. Sent your regards to me. I appreciated that.”
“Here it comes,” Grant told himself. Involuntarily his body tensed.
But nothing came.
Hellion waved his arm to indicate the mighty dome which nestled in another larger, deeper arena in the canyon. Through the quartz, even in the murkiness of the gray water, one could see the towering canyon walls that ran up from the ocean floor.
“Just like on the surface,” said Hellion proudly. “All the comforts of home. The boys like it down here. A few things to do and a good place to loaf around. Lamps that take the place of daylight, latest electrolysis equipment, generators—everything. We have it cozy.” He turned to face Grant squarely. “I wish you could stay with us a while,” he said, “but I suppose you will want to be going back.”
Grant gasped. “Why, yes,” he said. “The chief will be expecting me.”
But there was something wrong. No word or action. Nothing in the atmosphere. Nothing at all—except that Hellion Smith hated his guts. Hellion Smith wouldn’t let him walk out of this place and go back to the surface.