The last part of the cutting was the most delicate. A small part had to be untouched, so that the wiring which led up from below to the huge fan would not be severed. The instant Monk gave the go-ahead, the whole group joined in carefully lifting the head of the duct and laying it back on the concrete, where the fan continued to roar.
Frug had already strapped a leather harness around his waist and chest. One end of the nylon rope was attached to the harness. Bishop was clamping a frictionless roller to the jagged edge of raw metal on the lip of the duct.
“All right, Frug, over you go,” said Warlock. “Let him down gently, boys. Have those sleep-darts ready, Frug.”
Simon peered down into the duct as he took a hold on the rope. Three hundred feet below he could make out a smudge of light: the illumination of the vault coming through the outlet grille.
Frug disappeared down the great dark throat like a fly descending into a bassoon.
“Easy does it,” Warlock mumbled. “Don’t bounce him about down there. Mustn’t have any noise.”
After some time a section of the taut rope marked with red tape passed through Simon’s hands.
“There’s the warning,” whispered Bishop. “He’s almost there.”
“Steady now.”
Warlock let the other three men support the weight on the rope while he felt the strand like a doctor testing a patient’s pulse.
“Now, lower away a fraction of an inch at a time. Stop immediately when I feel the tug... A bit more... Now, stop!”
Frug had signalled that he was in position behind the grille, which gave his sight and his dart gun access to the vault. Motionless, the men at the surface waited. They could hear nothing but the roar of the fan beside them, and like fishermen they poured all their consciousness into their sense of touch to judge by slight pulls on the line what was happening far below.
At last there were three definite jerks on the rope, which meant that Frug had knocked out the vault guards and would be removing the grille while the rope and harness were drawn back up for use in Bishop’s descent. The line went slack and as Bishop and Monk hauled it up Simon took one last look around through his coated glasses and inconspicuously removed them. He was going to try to make use of the infra-red beam across the recessed doorway after all, and he did not want the glasses to arouse suspicion.
A moment later, Bishop was in harness and ready for his descent. Simon was ready too. The next few minutes would contain that precise instant in which he alone would take fate in his hand and twist it to his own will... or else find that fate was not so flexible, and that its revenge for such a challenge was death.
3
The Saint estimated the amount of rope being fed down into the duct with Bishop dangling at the end of it. This time there was less tense caution in the operation and more haste. Frug would not quite have taken the grille off the mouth of the duct by now. Bishop was about a hundred feet from the bottom.
“Wait!” Simon whispered suddenly.
He froze, looking towards the rear of the building. Monk and Warlock froze too, their eyes wide. Bishop was left temporarily suspended in the duct.
“What is it?” Warlock breathed.
“Somebody there?” asked Monk.
“I thought I saw somebody,” the Saint answered.
“If you’re trying to...” Warlock began.
“I’m not trying to do anything, but I don’t fancy getting shot standing here like a goat on a tether. Shall I go look?”
“Oh, no, you don’t!” Warlock growled. “You and Monk hang on here.”
Simon smiled underneath the grim expression he had to keep like a mask on his face. He felt like a chess player who has just set up his unsuspecting opponent for an inescapable forking trap: in denying Simon the chance to leave the rope, a chance Simon would gladly have accepted, Warlock had opened himself to an equally catastrophic possibility.
“Stick close to the wall,” Simon cautioned.
Warlock had drawn his pistol. He edged along the side of the dome, keeping his back close against it. The recessed doorway was only a few feet ahead of him. He stopped and looked back, shaking his head as if ready to call off his search. Simon urged him on with desperate motions of his own head. Warlock moved further along the wall. When he was directly outside the recessed door, the Saint struck.
“Look out!” he shouted.
Warlock stumbled back into the doorway in a panic-stricken dive for cover. Instantly there was a tumultuous clamour of bells and sirens. Even Simon, who was expecting the uproar, and possibly worse, felt something like a galvanic shock from the tip of his tongue to his toes. Monk very nearly jumped straight in the air, though his fingers automatically clung to the rope.
Warlock was staggering from the doorway, coughing, rubbing his eyes wildly with one hand as he waved his pistol with the other. A thin mist was spraying from around the locked steel door, apparently a gas meant to blind and otherwise incapacitate a would-be intruder temporarily.
“Help me!” was the most Warlock could manage to cry as he stumbled against the railing, almost into the mine field, and then back towards the wall of the building.
Monk’s eyes were gigantic with surprise and fear, and he stood as if he had suddenly been frozen solid, his huge hands clinging numbly to the rope.
“What is it? What is it?” he croaked.
“Time you were left holding the bag,” Simon answered.
He released his own grip on the rope and threw himself towards Warlock. The fat man, still blinded and having lost all sense of direction, was standing with his broad back towards the ventilation ducts. The target was too tempting to resist, particularly when every second was vital. The Saint hurled himself like a wrestler catapulting the full weight of his body off the ropes at his opponent. His right shoulder smashed into the centre of Warlock’s back and sent him sprawling on his face. The pistol which was Simon’s main goal scooted from Warlock’s hand across the concrete walk and three feet out on to the grass at the edge of the mine field. Since it touched no infra-red beams it set off no explosion, but in order to get it Simon would have had to prostrate himself on the walkway and stretch his arm carefully under the low beams.
He did not have time even to consider that possibility, for within a second or two after Warlock hit the pavement a new and chilling sound joined the howl of sirens and clanging of bells. It was Bishop’s shriek of helpless horror as he plummeted down the duct like a stone.
Simon whirled from Warlock’s floundering form to see Monk, his hands free, lurch towards him from the beheaded extractor vent. The tail end of the rope was uncoiling rapidly from the ground and disappearing over the edge of the vent’s mouth. Bishop’s agonized cry, just before it was suddenly cut short, was joined by a brief and quickly truncated squawk from Frug, who had apparently been unable to get out into the vault in time to avoid breaking his comrade’s fall.
The Saint dodged and ducked as Monk’s arm swung at him with all the weight of an oak log. He chopped the huge man in the kidneys and sent him reeling against the wall of the building. But Monk, however much like a clumsy gorilla he might look at other times, proved surprisingly agile when fighting for his life. Without a second’s delay he rebounded from the wall and got off a left and a right jab at Simon, either of which could have taken off the head of a marble statue if it had landed squarely. But the Saint managed to counter the left and take the right on his shoulder. Now he was knocked back to the wall, and Monk dived at him. Simon rolled aside, yanked Monk’s wrist, and swung him heavily against the concrete dome.