That is the essential point, of course—Thorn Hard's work with the Watch. His job was, officially, hanging somewhere above the twenty-thousand-foot level with his detector-screens out, listening for unauthorized traffic. And, the normal state of affairs between the Com-Pubs and the United Nations being one of highly armed truce, "unauthorized traffic" meant nothing more or less than spies.
But on August 19th, 2037, Thorn Hard was off duty. Decidedly so. He was sitting on top of Mount Wendel, in the Rockies; he had a ravishingly pretty girl sitting on the same rock with him, and he was looking at the sunset. The plane behind him was an official Watch plane, which civilians are never supposed to catch a glimpse of. It had brought Thorn Hard and Sylva West to this spot. It waited now, half-hidden by a spur of age-eroded rock, to take them back to civilization again. Its G.C. (General Communication) phone muttered occasionally like the voice of conscience.
The colors of the mountain changed and blended. The sky to westward was a glory of a myriad colors. Man and girl, high above the world, sat with the rosy glow of dying sunlight in their faces and watched the colors fade and shift into other colors and patterns even more exquisite. Their hands touched. They looked at each other. They smiled queerly, as people smile who are in love or otherwise not quite sane. They moved inevitably closer....
And then the G.C. phone barked raucously:
"All Watch planes attention! Urgent! Extreme high-level traffic reported seven-ten line bound due east, speed over one thousand. All Watch planes put out all detectors and use extra vigilance. Note: the speed, course, and time of report of this traffic checks with Com-Pub observations of moving objects approaching Earth from Mars. This possibility should be considered before opening fire."
Thorn Hard stiffened all over. He got up and swung down to the stubby little ship with its gossamer-like wings of cellate. He touched the report button.
"Plane 257-A reporting seven-ten line. Thorn Hard flying. On Mount Wendel, on leave. Orders?"
He was throwing on the screens even as he reported. And the vertical detector began to whistle shrilly. His eyes darted to the dial, and he spoke again.
"Added report. Detector shows traffic approaching, bound due east, seven hundred miles an hour, high altitude.... Correction; six-fifty miles. Correction; six hundred." He paused. "Traffic is decelerating rapidly. I think, sir, this is the reported ship."