Jan leaned against the elephant and rested his hands on the skin, rough as the bark of a tree. He looked at the great tusks and the curving trunk, caught by the skill of the taxidermist in the moment of challenge or salutation. What still weirder creatures, he wondered, from what unknown worlds would one day be looking at this exile from Earth?

"How many animals have you sent the Overlords?" he asked Rupert.

"At least fifty, though of course this is the biggest one. He's magnificent, isn't he? Most of the others have been quite small-butterflies, snakes, monkeys, and so on. Though I did get a hippo last year."

"It's a morbid thought, but I suppose they've got a fine stuffed group of Homo sapiens in their collection by this time. I wonder who was honoured?"

Jan gave a wry smile.

"What would happen," continued Jan thoughtfully, "if someone volunteered to go as a live specimen? Assuming that an eventual return was guaranteed, of course."

"You're probably right," said Rupert, rather indifferently. "It would be easy to arrange through the hospitals."

Rupert laughed, though not unsympathetically.

"Is that an offer? Shall I put it to Rashaverak?"

For a moment Jan considered the idea more than half seriously. Then he shook his head.

"He called me up about six weeks ago. He'd just found book I'd been hunting. Rather nice of him."

"Did you ever discover what he was looking for?" he asked. "I mean, it seems so hard to reconcile the Overlords' science with an interest in the occult."

"Er -- no. I was only thinking out loud. They'd certainly turn me down. By the way, do you ever see Rashaverak these days?"

Rupert looked at Jan a little suspiciously, wondering if his brother-in-law was poking fun at his hobby.

Jan walked slowly round the stuffed monster, admiring the skill that had frozen it forever at this instant of greatest vigour.

"His explanation seemed adequate. As an anthropologist he was interested in every aspect of our culture. Remember, they have plenty of time. They can go into more detail than a human research worker ever could. Reading my entire library probably put only a slight strain on Rashy's resources."

"Incidentally," said Rupert, changing the subject abruptly, "if you think this is a big job, you should see the commission Sullivan's got. He's promised to deliver the two biggest creatures of all -- a sperm whale and a giant squid. They'll be shown locked in mortal combat. What a tableau that will make!"

For a moment Jan did not answer. The idea that had exploded in his mind was too outrageous, too fantastic to be taken seriously. Yet, because of its very daring, it might succeed.

That might be the answer, but Jan was not convinced. Sometimes he had thought of confiding his secret to Rupert but his natural caution had held him back. When he met his Overlord friend again, Rupert would probably give something away -- the temptation would be far too great.

"What's the matter?" said Rupert anxiously. "The heat getting you down?"

Jan shook himself back to present reality.

"Oh," said Rupert, "one of those cargo ships of theirs will come down, open a hatch, and hoist it in."

"I'm all tight," he said. "I was just wondering how the Overlords would collect a little packet like that."

It might have been the cabin of a spaceship, but it was not. The walls were covered with meters and instruments: there were no windows -- merely a large screen in front of the pilot. The vessel could carry six passengers, but at the moment Jan was the only one. He was watching the screen intently, absorbing each glimpse of this strange and unknown region as it passed before his eyes. Unknown -- yes, as unknown as anything he might meet beyond the stars, if his mad plan succeeded. He was going into a realm of nightmare creatures, preying upon each other in a darkness undisturbed since the world began. It was a realm above which men had sailed for thousands of years: it lay no more than a kilometre below the keels of their ships -- yet until the last hundred years they had known less about it than the visible face of the moon.

The pilot was dropping down from the ocean heights, towards the still unexplored vastness of the South Pacific Basin. He was following, Jan knew, the invisible grid of sound waves created by beacons along the ocean floor. They were still sailing as far above that floor as clouds above the surface of the Earth… There was very little to see: the submarine's scanners were searching the waters in vain. The disturbance created by their jets had probably scared away the smaller fish: if any creature came to investigate, it would be something so large that it did not know the meaning of fear.

"That," said Jan, "is exactly what I thought."

It took only a moment to check their position on the sonar grid. When he had finished with his instrument readings, the pilot remarked: "Before we start the motors again, let's see if we can hear anything."

"Time to get a fix," said the pilot. He threw a set of switches, and the submarine came to rest in a gentle surge of deceleration as the jets ceased their thrust. The vessel was motionless, floating in equilibrium as a balloon floats in the atmosphere.

The loudspeaker flooded the quiet little room with a low, continuous murmur of sound. There was no outstanding noise that Jan could distinguish from the rest. It was a steady background, into which all individual sounds had been blended. He was listening, Jan knew, to the myriad creatures of the sea talking together. It was as if he stood in the centre of a forest that teemed with life -- except that there he would have recognized some of the individual voices. Here, not one thread in the tapestry of sound could be disentangled and identified. It was so alien, so remote from anything he had ever known, that it set Jan's scalp crawling. And yet this was part of his own world. The shriek cut across the vibrating background like a flash of lightning against a dark storm cloud. It faded swiftly away Into a banshee wail, an ululation that dwindled and died, yet was repeated a moment later from a more distant source. Then a chorus of screams broke out, a pandemonium that caused the pilot to reach swiftly for the volume control.

The tiny cabin vibrated with power -- the power which could hold at bay the immense weight of the waters above their heads, and could create this little bubble of light and air within which men could live. If that power failed, thought Jan, they would become prisoners in a metal tomb, buried deep in the silt of the ocean bed.

'What in the name of God was that?" gasped Jan.

"Weird, isn't it? It's a school of whales, about ten kilometres away. I knew they were in the neighbourhood and thought you'd like to hear them."

"And I always thought the sea was silent! Why do they make such a din?"

A fish with incredibly exaggerated jaws was visible in the viewing screen. It appeared to be quite large, but as Jan did now know the scale of the picture it was bard to judge. Hanging from a point just below its gills was a long tendril, ending In an unidentifiable, bell-shaped organ.

Jan shuddered.

"We're seeing it on infrared," said the pilot. "Let's look at the normal picture."

"Talking to one another, I suppose. Sullivan could tell you -- they say he can even identify some individual whales, though I find that hard to believe. Hello, we've got company!"

The fish vanished completely. Only the pendant remained, glowing with its own phosphorescence. Then, just for an instant, the shape of the creature flickered into visibility as a line of lights flashed out along its body.

The cabin vibrated once again as the vessel eased itself forward. The great luminous fish suddenly flashed on all its lights in a frantic signal of alarm, and departed like a meteor Into the darkness of the abyss.

"It's an angler: that's the bait it uses to lure other fish. Fantastic, Isn't it? What I don't understand is -- why doesn't his bait attract fish big enough to eat him? But we can't wait here all day. Watch him run when I switch on the jets."

It was after another twenty minutes of slow descent that the Invisible fingers of the scanner beams caught the first glimpse of the ocean bed. Far beneath, a range of low hills was passing, their outlines curiously soft and rounded. Whatever irregularities they might once have possessed had long ago been obliterated by the ceaseless rain from the watery heights above. Even here in mid-Pacific, far from the great estuaries that slowly swept the continents out to sea, that rain never ceased. It came from the storm-scarred flanks of the Andes, from the bodies of a billion living creatures, from the dust of meteors that had wandered through space for ages and had come at last to rest. Here in the eternal night, it was laying the foundations of the lands to be.

The submarine continued on its gentle downward glide. Now another picture was beginning to form on the screen: because of the angle of view, it was some tune before Jan could interpret what he saw. Then he realized that they were approaching a submerged mountain, jutting up from the hidden plain.

"Nearly there," said the pilot. "You'll be able to see the lab in a minute."

The hills drifted behind. They were the frontier posts, as Jan could see from the charts, of a wide plain which lay at too great a depth for the scanners to reach.

The picture was clearer now: at this short range the definition of the scanners improved and the view was almost as distinct as if the image was being formed by light-waves. Jan could see fine detail, could watch the strange fish that pursued each other among the rocks. Once a venomous-looking creature with gaping jaws swam slowly across a half-concealed cleft. So swiftly that the eye could not follow the movement, a long tentacle flashed out and dragged the struggling fish down to its doom.

"That," said the pilot indifferently, "is probably Lucifer. Someone's been feeding him again." He threw a switch and leaned over the control desk.

"What's that?" gasped Jan suddenly. He pointed a shaky finger towards the nearest sphere. The curious pattern of lines on its surface had resolved itself into a network of giant tentacles. As the submarine came closer, he could see that they ended in a great, pulpy bag, from which peered a pair of enormous eyes.

They were travelling slowly above a spur of rock jutting out from the base of the mountain. The plain beneath was now coming into view: Jan guessed that they were not more than a few hundred metres above the sea-bed. Then he saw, a kilometre or so ahead, a cluster of spheres standing on tripod legs, and joined together by connecting tubes. It looked exactly like the tanks of some chemical plant, and indeed was designed on the same basic principles. The only difference was that here the pressures which had to be resisted were outside, not within.

"S.2 calling Lab. I'm connecting up. Will you shoo away your pet?" The reply came promptly.

"Lab to S.2. O. K. -- go ahead and make contact. Lucey will get out of the way."

Jan found Professor Sullivan in a small, untidy room that seemed to combine the attributes of office, workshop and laboratory. He was peeping through a microscope into what looked like a small bomb. Presumably it was a pressure-capsule containing some specimen of deep-sea life, still swimming happily around under its normal tons-to-the-square-centimetre conditions.

The curving metal walls began to fill the screen. Jan caught a last glimpse of a giant, sucker-studded arm whipping away at their approach. Then there was a dull clang, and a series of scratching noises as the clamps sought for their locking points on the submarine's smooth, oval hull. In a few minutes the vessel was pressed tightly against the wall of the base, the two entrance ports had locked together, and were moving forward through the hull of the submarine at the end of a giant hollow screw. Then came the "pressure equalized" signal, the batches unsealed, and the way into Deep Sea Lab One was open.

"Rupert's fine," replied Jan. "He sends his best wishes, and says he'd love to visit you if it weren't for his claustrophobia."

"Well," said Sullivan, dragging himself away from the eyepiece. "How's Rupert? And what can we do for you?"

"No more than being in a stratoliner. If anything went wrong, the result would be the same in either case."

"That's the sensible approach, but it's surprising how few people see it that way." Sullivan toyed with the controls of his microscope, then shot Jan an inquisitive glance.

"I'll be very glad to show you around," he said, "but I must confess I was a little surprised when Rupert passed on your request. I couldn't understand why one of you spacehounds should be interested in our work. Aren't you going in the wrong direction?" He gave a chuckle of amusement. "Personally, I've never seen why you were in such a hurry to get out there. It will be centuries before we've got everything in the oceans nicely charted and pigeonholed."

"Then he'd certainly feel a little unhappy down here, with five kilometres of water on top of him. Doesn't it worry you, by the way?"

Jan shrugged his shoulders.

Jan took a deep breath. He was glad that Sullivan had broached the subject himself; for it made his task that much easier. Despite the ichthyologist's jest, they had a great deal in common. It should not be too hard to build a bridge, to enlist Sullivan's sympathy and aid. He was a man of imagination, or he would never have invaded this underwater world. But Jan would have to be cautious, for the request he was going to make was, to say the least of it, somewhat unconventional.

"Exceedingly annoyed, no doubt."

"I'm sure you would. And suppose, one day, you had a chance of achieving your goal, without them knowing, what would you do? Would you take the opportunity?"

There was one fact that gave him confidence. Even if Sullivan refused to co-operate, he would certainly keep Jan's secret. And here in this quiet little office on the bed of the Pacific, there seemed no danger that the Overlords -- whatever strange powers they possessed -- would be able to listen to their conversation.

"Professor Sullivan," he began, "if you were interested in the ocean, but the Overlords refused to let you go near it, how would you feel?"

Sullivan never hesitated.

"Of course. And argue later." Right into my hands thought Jan. He can't retreat now -- unless he's afraid of the Overlords. And I doubt if Sullivan is afraid of anything. He leaned forward across the cluttered table and prepared to present his case.

Professor Sullivan was no fool. Before Jan could speak, his lips twisted into a sardonic smile. "So that's the game, is it?" he said slowly. "Very, very Interesting! Now you go right ahead and tell me why I should help you."