Avery must have had a fairly tight grip on his own weapon, because when Karnes' slug hit him, it went off once before his body spread itself untidily across the freshly set cement. Then the gun fell out of the dead hand and slid a few feet, spinning in silly little circles. Karnes approached the corpse cautiously, just in case it wasn't a corpse, but it took only a moment to see that the caution had been unnecessary. He knelt, rolled the body over, unfastened the pants, pulled them down to the knees and stripped off the ribbon of adhesive tape that he knew would be on the inside of the thigh. Underneath it were four little squares of thin plastic. As he looked at the precious microfilm in his hand, he sensed something odd. If he had been equipped with the properly developed muscles to do so, he would have pricked his ears. There was a soft footstep behind him. He spun around on his heel, his gun ready. There was another man standing at the top of the shadowy stairway. Karnes stood up slowly, his weapon still levelled. "Come down from there slowly, with your hands in the air!" The man didn't move immediately, and, although Karnes couldn't see his face clearly in the shimmering shadows, he had the definite impression that there was a grin on it. When the man did move, it was to turn quickly and run down the upper hallway, with a shot ringing behind him. Karnes made the top of the stairway and sent another shot after the fleeing man, whose outline was easily visible against the pre-dawn light that was now beginning to come in through a window at the far end of the hall. The figure kept running, and Karnes went after him, firing twice more as he ran. _Who taught you to shoot, dead-eye?_ he thought, as the man continued to run. At the end of the hall, the man turned abruptly into one of the offices-to-be, his pursuer only five yards behind him. * * * * * Afterwards, Karnes thought it over time after time, trying to find some flaw or illusion in what he saw. But, much as he hated to believe his own senses, he remained convinced. The broad window shed enough light to see everything in the room, but there wasn't much in it except for the slightly iridescent gray object in the center. It was an oblate spheroid, about seven feet high and eight or nine feet through. As Karnes came through the door, he saw the man step _through_ the seemingly solid material into the flattened globe. Then globe, man and all, vanished. The room was empty. Karnes checked his headlong rush into the room and peered around in the early morning gloom. For a full minute his brain refused even to attempt rationalizing what he had seen. He looked wildly around, but there was no one there. Suddenly he felt very foolish. _All right. So men can run into round gray things and vanish. Now use a little sense and look around._