Then, angrily, he turned and said something at the door of the helicopter, and a second head appeared. There was a short discussion that Dave could not hear, and then the second man came out carrying a tool kit and headed for the lab. The first man got back into the helicopter and took off towards the main building. Dave nodded. It was reasonable to suppose that Claverly, and then Phelps, after finding themselves in this half-world alone, had gone back to the main laboratory to see if they could raise the attention of their friends. Dave himself could have been expected to follow, running after the jeep that had taken the others back to their lab. The hunter expected to find Dave wandering disconsolately around the other lab. When the helicopter had disappeared, Dave arose and scuttled across the plain towards the building he had left. He felt like a battleship on a clear ocean in broad daylight trying to slink unseen behind an enemy, but there seemed no way to avoid it. At any rate, the workman was paying no attention to his surroundings. Within the walls of the laboratory, the workman was unlimbering his tool kit. He was an efficient workman. It was his job to repair the television camera and it was his cohort's job to track down and dispose of Dave. He went to work on this basis and ignored the possibility that Dave might be stalking him—until Dave came silently up behind him and kicked the small sectional ladder out from beneath the workman's feet. Dave's fist came plunging through the windmill of flying arms and legs and connected solidly beneath the workman's ear. Startled, off-balance, and then slugged, the workman came to earth with a dull thud and sprawled motionless. Dave snarled and made doubly sure with a thrusting heel-kick against the workman's jaw and throat. The workman was not the first man to die from such a kick. Then, in a matter of minutes, Dave was wearing the dead workman's shirt and trousers and was plying the tools on the television camera deftly. Dave had not wrecked the thing, he had just swung his weight against its moorings and displaced it. The problem was simple, and was handled by a couple of adjustable end-wrenches. It could have been done by sheer strength, but not with the desired precision. So Dave loosened the nuts that held the flexible couplings and slid the camera back into its original perfect registry with the camera in the real world. He was tightening the nuts again when he heard the helicopter returning. Dave stooped and packed