Summary:

Within the earth's core, lives an advanced race who have created an offspring. This offspring (the Dweller) gradually turns from good to evil, and at times will rise to the surface of the earth to capture men and women. Scientist Dr Goodwin and pilot Larry O'Keefe follow the Dweller down and O'Keefe finds himself caught between the attentions of two beautiful women; one good, one evil.

Excerpt:

For two months I had been on the d'Entrecasteaux Islands gathering data for the concluding chapters of my book upon the flora of the volcanic islands of the South Pacific. The day before I had reached Port Moresby and had seen my specimens safely stored on board the Southern Queen. As I sat on the upper deck I thought, with homesick mind, of the long leagues between me and Melbourne, and the longer ones between Melbourne and New York.

It was one of Papua's yellow mornings when she shows herself in her sombrest, most baleful mood. The sky was smouldering ochre. Over the island brooded a spirit sullen, alien, implacable, filled with the threat of latent, malefic forces waiting to be unleashed. It seemed an emanation out of the untamed, sinister heart of Papua herself—sinister even when she smiles. And now and then, on the wind, came a breath from virgin jungles, laden with unfamiliar odours, mysterious and menacing.

It is on such mornings that Papua whispers to you of her immemorial ancientness and of her power. And, as every white man must, I fought against her spell. While I struggled I saw a tall figure striding down the pier; a Kapa-Kapa boy followed swinging a new valise. There was something familiar about the tall man. As he reached the gangplank he looked up straight into my eyes, stared for a moment, then waved his hand.

And now I knew him. It was Dr. David Throckmartin—"Throck" he was to me always, one of my oldest friends and, as well, a mind of the first water whose power and achievements were for me a constant inspiration as they were, I know, for scores other.

Coincidentally with my recognition came a shock of surprise, definitely—unpleasant. It was Throckmartin—but about him was something disturbingly unlike the man I had known long so well and to whom and to whose little party I had bidden farewell less than a month before I myself had sailed for these seas. He had married only a few weeks before, Edith, the daughter of Professor William Frazier, younger by at least a decade than he but at one with him in his ideals and as much in love, if it were possible, as Throckmartin. By virtue of her father's training a wonderful assistant, by virtue of her own sweet, sound heart a—I use the word in its olden sense—lover. With his equally youthful associate Dr. Charles Stanton and a Swedish woman, Thora Halversen, who had been Edith Throckmartin's nurse from babyhood, they had set forth for the Nan-Matal, that extraordinary group of island ruins clustered along the eastern shore of Ponape in the Carolines.

I knew that he had planned to spend at least a year among these ruins, not only of Ponape but of Lele—twin centres of a colossal riddle of humanity, a weird flower of civilization that blossomed ages before the seeds of Egypt were sown; of whose arts we know little enough and of whose science nothing. He had carried with him unusually complete equipment for the work he had expected to do and which, he hoped, would be his monument.

What then had brought Throckmartin to Port Moresby, and what was that change I had sensed in him?

Hurrying down to the lower deck I found him with the purser. As I spoke he turned, thrust out to me an eager hand—and then I saw what was that difference that had so moved me. He knew, of course by my silence and involuntary shrinking the shock my closer look had given me. His eyes filled; he turned brusquely from the purser, hesitated—then hurried off to his stateroom.

"'E looks rather queer—eh?" said the purser. "Know 'im well, sir? Seems to 'ave given you quite a start."

I made some reply and went slowly up to my chair. There I sat, composed my mind and tried to define what it was that had shaken me so. Now it came to me. The old Throckmartin was on the eve of his venture just turned forty, lithe, erect, muscular; his controlling expression one of enthusiasm, of intellectual keenness, of—what shall I say—expectant search. His always questioning brain had stamped its vigor upon his face.

But the Throckmartin I had seen below was one who had borne some scaring shock of mingled rapture and horror; some soul cataclysm that in its climax had remoulded, deep from within, his face, setting on it seal of wedded ecstasy and despair; as though indeed these two had come to him hand in hand, taken possession of him and departing left behind, ineradicably, their linked shadows!

Yes—it was that which appalled. For how could rapture and horror, Heaven and Hell mix, clasp hands—kiss?

Yet these were what in closest embrace lay on Throckmartin's face!

Deep in thought, subconsciously with relief, I watched the shore line sink behind; welcomed the touch of the wind of the free seas. I had hoped, and within the hope was an inexplicable shrinking that I would meet Throckmartin at lunch. He did not come down, and I was sensible of deliverance within my disappointment. All that afternoon I lounged about uneasily but still he kept to his cabin—and within me was no strength to summon him. Nor did he appear at dinner.