The Outcasts of Solar III

Of all Terra's bloodily brawling billions, only mighty scientist Jon Saxon sensed the Others. Even as he swung his fists and dodged the tearing dart guns, his skin crawled weirdly. Who— who —was so coldly watching this war-torn, hell-bent planet?
Quiet! Jon Saxon's voice was a breath in the night as he cautioned the girl. A warning prickle of danger had run over his skin like gooseflesh. He was a big man, over six feet, with thick brawny shoulders and arms like a blacksmith. Before the girl could cry out, Saxon swept her into the deep shadow of a doorway. His dark gray eyes probed the street but he could see no one.
This seventh level thoroughfare of Adirondaka appeared utterly deserted. Only occasional street lamps revealed glimpses of the magnificent architecture of the post-atom capitol of Earth. Down the center of the boulevard the public conveyor swept silently, endlessly without a passenger anywhere along its ribbon-like length.
Where are they? the girl whispered.
He shook his head. I can't see them. But his skin continued to prickle its warning. Somewhere in the shadows were men, several of them, stalking him soundlessly.
He became aware of an alien quality about the figures ringing in him and the girl, figures he could sense but not see. Still nothing moved in the street. The girl, he realized, was strangely quiescent.
Then, sharp as speech, her thought impinged on Jon Saxon's consciousness. The fools! And after I told Emil not to let them crowd him!
Jon Saxon's eyes narrowed. So the girl thought the invisible figures were G.A.'s men. He had known, of course, from their first meeting that the girl was a General Atomic spy. But by not so much as a hint had he let her suspect that her very thoughts betrayed her.
The tingling sensation intensified, warned him that the shadows were closing in. The feel of alienism was stronger, as if they were not quite human. His heart pumped faster, the pulse throbbing in his ears.
The moon was rising, he saw, competing indifferently with the street lights. Its rays streamed down through the ninety-eight levels of the capitol, down through crystal plastic roadways into the dense blackness of the pit itself.