Strangers

planes, among other things. In addition to 2.4 billion dollars of equipment and materiel - freeze-dried food, medicine, portable field hospitals, clothing, blankets, tents, handguns, rifles, mortars, field artillery, ammunition, light military vehicles such as Jeeps and armored personnel carriers, and twenty backpack nukes - the vast storage dump contained a variety of useful aircraft. First, the helicopters: thirty Sikorsky S-67 Blackhawk antitank gunships; twenty Bell Kingcobras; eight Anglo-French Westland Pumas, general purpose transports; and three big Medevac choppers. No conventional aircraft were stored at Thunder Hill, but there were twelve vertical takeoff jets of the type manufactured in England by Hawker Siddeley and known there as Harriers, but which were called AV-8As when in U S. service. Because the Harriers were equipped with powerful vectored-thrust engines, the craft could land and take off vertically, without need of a runway. In a grave crisis - for example, subsequent to a limited nuclear strike and a land invasion by enemy troops - the aircraft of Thunder Hill, both choppers and Harriers, could be lifted to the top level, rolled out through the massive blast doors, and sent hurtling into the sky.
        However, the current crisis did not involve war or require the unleashing of the Depository's aircraft, so Leland and the lieutenant bypassed the two immense elevators. They also passed the two smaller but still oversize cargo elevators, their footsteps echoing off the stone walls, and took one of the three smallest cabs - about the size of a standard lift in a hotel - down into the bowels of Thunder Hill.
        Medical supplies, food, guns, and all ammunition were stored on the third level, the bottom floor of the complex, in a network of chambers which had been caulked, equipped with pressure-release bores, and fitted with doors for the purpose of blast containment. On the second - the middle - level, all the vehicles and aircraft were kept in other huge caverns, and it was there, too, that the staff lived and worked.
        Leland and Lieutenant Horner got off the lift at the second level. They stepped into a lighted, circular, rock-wall chamber three hundred feet in diameter. It served as a hub - in fact, personnel called it The Hub - from which four other caverns opened; and still more rooms lay beyond those four. The larger of those deep vaults contained - among other things - the aircraft, Jeeps, and armored personnel carriers.
        There were no doors on three of the four caverns which led off The Hub, for there was no serious danger of fire or explosion on that level. But the fourth chamber did, indeed, have doors, for it contained the secret of July 6, which Leland and many others had conspired to conceal. He stopped now, a few steps out of the elevator, to study those portals, which were twenty-six feet high and sixty-four feet wide. They were made of cross-braced two-by-fours rather than steel, because they had been jerry-built to meet an emergency situation; there had been no time to order a fabricated metal door to close off the cavern. They reminded the colonel of the enormous wooden doors in the wall that had protected the frightened natives from the beast on the other half of their island in the original King Kong. Considering what lay behind these doors, that horror-movie image did not inspire confidence. Leland shuddered.
        Lieutenant Horner said, "Still gives you the creeps, huh?"
        "You mean you're comfortable with it now?"
        "Hell, no, sir. Hell, no."
        Inset in the bottom of one of those huge wooden barriers was a much smaller, man-sized door through which researchers entered and exited the room beyond. An armed guard was positioned there to allow entrance only to those with the proper pass. The activities in that forbidden chamber had nothing to do with the other - primary - functions of the Depository, and ninety percent of the personnel were not permitted access to the area. Indeed, ninety percent did not know what was in that cavern.
        Around the circumference of The Hub, between the openings to other caverns, buildings had been erected along the walls and anchored to the rock. The structures dated to the first year of the Depository's construction, back in the early 1960s. Then, they had served as offices for engineers, superintendents, and the Army's project officers. Over the years, an entire subterranean town had been