A month later, or maybe two months, and they could not have done it. The grids would have been up, and any Throg ship venturing into Warlock's amber-tinted sky would abruptly cease to be. In the race for survival as a galactic power, Terra had that one small edge over the swarms of the enemy. They need only stake out their new-found world and get the grids assembled on its surface; then that planet would be locked to the beetles. The critical period was between the first discovery of a suitable colony world and the erection of grid control. Planets in the past had been lost during that time lag, just as Warlock was lost now. Throgs and Terrans ... For more than a century now, planet time, they had been fighting their queer, twisted war among the stars. Terrans hunted worlds for colonization, the old hunger for land of their own driving men from the over-populated worlds, out of Sol's system to the far stars. And those worlds barren of intelligent native life, open to settlers, were none too many and widely scattered. Perhaps half a dozen were found in a quarter century, and of that six maybe only one was suitable for human life without any costly and lengthy adaption of man or world. Warlock was one of the lucky finds which came so seldom. Throgs were predators, living on the loot they garnered. As yet, mankind had not been able to discover whether they did indeed swarm from any home world. Perhaps they lived eternally on board their plate ships with no permanent base, forced into a wandering life by the destruction of the planet on which they had originally been spawned. But they were raiders now, laying waste defenseless worlds, picking up the wealth of shattered cities in which no native life remained. And their hidden temporary bases were looped about the galaxy, their need for worlds with an atmosphere similar to Terra's as necessary as that of man. For in spite of their grotesque insectile bodies, their wholly alien minds, the Throgs were warm-blooded, oxygen-breathing creatures. After the first few clashes the early Terran explorers had endeavored to promote a truce between the species, only to discover that between Throg and man there appeared to be no meeting ground at all--total differences of mental processes producing insurmountable misunderstanding. There was simply no point of communication. So the Terrans had suffered one smarting defeat after another until they perfected the grid. And now their colonies were safe, at least when time worked in their favor. It had not on Warlock. A last vivid lash of red cracked over the huddle of domes in the valley. Shann blinked, half blinded by that glare. His jaws ached as he unclenched his teeth. That was the finish. Breathing raggedly, he raised his head, beginning to realize that he was the only one of his kind left alive on a none-too-hospitable world controlled by enemies--without shelter or supplies.