These panic-stricken humans ran silently, except for the gasps which burst from tortured throats. Abandoned children sobbed as they ran, not knowing nor caring where they went--driven by the fear of what was behind them. Behind them, flames from burning houses were growing brighter and dull explosions were growing louder. Soon there were no more humans running, but as Wing Commander Curt Wing and Dead-Eye plodded on, they saw charred and broken corpses and the smell of burnt flesh was mingling with the stench of wood and plastic and paint. And then Wing and Dead-Eye saw _Them_. _They_ numbered in the hundreds--spreading in a long single line--moving sluggishly but steadily, bolts of blue flame flaring out ahead of them. The flashing blue bolts melted steel, sent plastic into exploding drops of fire, touched and charred humans who still moved in their path. Wing dragged Dead-Eye out of the deserted street into a low shop building. They moved to a window and watched those blue bolts leap overhead to jab at building or human somewhere back from where they had just come. "What are they?" Dead-Eye asked, peering at the thin line moving closer. "They're nothing but shadows, looks like." "Another dimension," Wing suggested. "Probably on a higher plane than our own. Maybe that's why they're just shadows to us." Dear God, he thought, what has humanity done to deserve this? We cannot fight them. We don't know what they are. Somehow, though, we must beat them. Earth must not die, not now, when we are on the very threshold of destiny. We've come from the mud and slime of a new born Earth, clawed and fought our way out of nothing to start reaching for the stars. Is this our destiny--to come so far and then be snuffed out before we even realize our talents? "We've got to beat them, Dead-Eye," Wing said harshly. "Don't worry, Cap," Dead-Eye urged. "Shucks, they can't be so tough that they can lick us. Besides, Cap, us Earthmen always fight better when the going's rough. Why, just give me and Elizabeth a chancet at them. We'll knock 'em dead." Wing's dark eyes were soft as they looked at Dead-Eye's earnest, bearded face. "We sure will, Dead-Eye," he said. "We sure will knock 'em dead." That is, Wing amended, staring at the relentless shadows as they moved slowly toward their haven, if _They_ don't knock us dead first. Wing and Dead-Eye hugged the buildings as they retreated. They picked their way along the rubble-strewn streets, their nostrils quivering at the intermingled odor of death, burnt flesh, charred and rain-wet wood. Ahead and behind them as they retreated, the flashing bolts of the shadow-things smashed buildings, leveled the trees along the boulevard, sending them up in puffs of white smoke and flame, heaving up the walks as tree roots exploded.