Because they had at one time or another visited each of the planets in their solar system and had exhausted their possibilities or found them barren, and because they were not equipped, even at the peak of their physical development, for intergalactic flight, there remained only one way to travel—in time.
Not forward or backward, for both had been tried. Travel ahead had been discouraging—in fact, it had convinced them that their normal passage through the years had to be stopped. The reason had been made dramatically clear—they, the master race, did not exist in the future. They had vanished and the lower forms of life had begun to take over.
Travel into the past would be even more boring than continued existence in the present, they realized, because they would be reliving the experiences they had had and still vividly remembered, and would be incapable of changing them. It would be both tiresome and frustrating.
That left only one way to go—sideways in time, across the dimension line—to a world like their own, but which had developed so differently through the eons that to visit it and conquer the minds of its inhabitants would be worth while.
In that way they picked Earth for their victim and sent out their spy. Just one spy. If he didn't return, they'd send another. There was enough time. And they had to be sure.
eorge put a record on the phonograph and fixed himself a drink while the machine warmed up.
The interdimensional invader reacted pleasurably to the taste and instant warming effect of the liquor on George's mind.
"Ahh!" said George aloud, and his temporary inhabitant agreed with him.