Dismissing the problem from his mind, he found a modest hotel overlooking the central square and checked in for the night.

Relatively, the field was a hive of activity when he arrived to claim his gear the following morning... the Icelandair flight was expected; a private, six-passenger Beechcraft Bonanza was being refueled at the avgas pump; the pilot of a small overhead-wing Cessna 150 was tying down his aircraft at the far end of the ramp. And above the terminal, an executive jet with Russian markings, which had just taken off, circled the field before it flew away toward the east. By the open doors of the freight shed, a forklift truck maneuvered crates of machinery onto a flatbed semi.

Bolan supervised the unloading of his own crates. The ultralight, powered by a 250 cc two-stroke engine positioned between the spars supporting the delta wing, was equipped with skis as well as landing wheels.

Bolan's kayak a Norwegian polymer version of the American Precision Mirage model, with a low deck and rounded gunwales was slung between the struts of the undercarriage.

High-energy iron rations, a goose-down sleeping bag, a ground pad, a wet suit, helmet and underwater boots were stowed in PVC sacks inside the kayak's fore and aft compartments along with the two paddles the warrior had chosen. The entire rig took less than half an hour to assemble.

After he had arranged for the ULM to be collected by helicopter from the sinkhole where he intended to drop beneath the ice to the source of the underground river, the Executioner took his place in the open bucket seat of the ultralight and requested permission for takeoff.

The flight had to be approved by the Icelandic coastguard service, and the official okay had come on condition that Bolan was equipped with two-way radio on which he could call for help in case of any accidents. Judging by the expression on the faces of the mechanics and laborers and customs officers gathered on the apron, local opinion seemed convinced that he would need to use it.

The tiny engine sputtered to life.

Polished spruce airscrew behind Bolan's seat spun, and the aircraft trundled out to the runway to await takeoff. A green light glowed from the control room above the terminal, and Bolan was on his way.

He had a flight of approximately seventy miles in front of him. For fifty of these he flew southwest, following the upstream course of the Jokulsa Fljotsdal river until it emerged from a terminal glacier on the fringe of the ice cap. Then he turned through twenty-two and a half degrees and vectored due west for the glacial region known as the Dyug Jujokull, where the sinkhole was located.

For the first few miles the ULM skimmed the surface of a lake, where the river had drowned a long, twisting valley. Then the land rose abruptly to a highland plateau bare of vegetation, an ancient volcanic wilderness that reminded Bolan in its empty desolation of a black Sahara.

So long as he was overflying the river valley, the Executioner kept the ultralight as low as he dared; even at one thousand feet the cold struck like a knife through the kapok-lined alpine survival suit and life belt that he wore. But when the barren rock bulk of the six-thousand-foot peak called Snafell materialized beneath a blanket of low cloud to his right, he hauled back the stick and sent the frail machine climbing high. There was no telling what hazardous combination of cold drafts and air pockets he could encounter above this icy terrain.

Lacking an oxygen mask, Bolan was becoming lightheaded when at last he saw, in the distance, the pale immensity of the frozen continent that was his target.

The Vatnajokull, eighty-three miles across and fifty from north to south, is an ice cap rather than a single Lacier. The surface, unexpectedly, is not blinding white but varies from gray through browns to a slate mauve.

Black lakes circle the southern margin and here, fissured away from the ice cliffs at the glacier's edge, float enormous bergs colored kingfisher blue and jade green in the cold northern light.

It took Bolan some time to locate the sinkhole. It was only when he flew to the terminal moraine from which the river he was to follow emerged and then banked through 180 degrees to track back toward the center of the ice mass, that he identified the dark opening in the frozen surface five hundred feet below.

The landing was rough. Jagged furrows crisscrossed the packed ice in all directions. The ultralight bounced once, twice and then, as the starboard ski snapped under a third impact, stewed sideways and slid for fifty yards, jolting the breath from the Executioner's body and bending one of the aluminum spars that acted as an engine support. Luckily the kayak was undamaged.

Bolan climbed down and began to dismantle the ULM. The sky was darkening ominously and he feared one of Iceland's sudden storms was brewing.

He was not mistaken. Within minutes angry clouds boiled overhead; the wind, penetratingly cold to start with, had howled up to gale force; and squalls of freezing snow lashed horizontally across the surface of the ice.

Bolan was forced to wait out the blinding blizzard. With wind and cold combining to produce a chill factor of minus-thirty-five degrees Fahrenheit, he rigged a hasty shelter from two paddles, the ultralight's unbroken ski and the red and yellow nylon of the machine's delta wing.

After an hour of frozen hell the wind dropped and the sky cleared. Shivering, Bolan emerged from his makeshift tent, unzippered one of his supply sacks and changed into his caver's rig. Beneath the life jacket he wore cellular inners, a Transat neoprene wet suit and a proofed coverall with builtin knee pads to minimize bruising against the inside of the canoe when shooting rapids.

Apart from the helmet, the total effect was much as though he had donned his familiar black-quit.

Eleven inches of snow had fallen during the storm. Bolan slid the kayak over to the edge of the sinkhole and busied himself with ice clamps, pitons and the arrangement of rope and pulleys that would allow him single-handed to lower himself and his craft into the depths.

The rig was in place before he heard the airplane.

Subconsciously he had for some time been aware of the approaching drone, but it was not until the pilot made his first pass over the cleft that Bolan registered the fact that he was under surveillance from above. It was a small aircraft of a type unfamiliar to him a V-tail, low-wing monoplane with a single motor in the nose. As it banked and turned for a second run, he could see through the spinning disk of the airscrew that there were two helmeted figures behind the Plexiglas canopy.

A coast-guard patrol, confirming that he had survived the long flight in the ULM? A meteorology crew checking out the results of the storm, astonished to see a human being in this wilderness? Or a private flyer from one of the many small fields that dotted the barren countryside?

It was only when the plane made its third pass skimming no more than twenty feet above the snow-covered ice that Bolan realized it carried no markings at all.

Half-deafened by the roar of the engine as it zoomed directly overhead, he watched the machine climb steeply and fly away toward the northeast.

What the hell?

The machine was as anonymous as the hardmen he had wasted in Reykjavik and elsewhere. Bolan tried to make a connection. Had the mystery pursuers latched on to him one more time? If they had, what would their next move be? Bolan shrugged away the questions.

The answers could wait. Right now he had more important things to do.

The sinkhole was like a huge inverted tunnel, 70 feet across at the top and more than 150 deep.

A freshening wind and freezing temperatures made the manipulation of ropes and tackle difficult for chilled hands topside. But within the shaft, which had been formed by steam from geothermal vents, the air was warm.