strange how a preconceived idea can affect a man's understanding of what he sees; seconds passed before Don could interpret the picture before his eyes—before he knew that, after all, he had come to the right place.
"Jesus!" he said softly. "I didn't know they grew that big." It was a shark, the largest he had ever seen. Its details were still obscured, but there was only one genus it could belong to. The whale shark and the basking shark might be of comparable size, but they were harmless her bivores. This was the king of all selachians— Carcharodon —the Great White Shark. Don tried to recall the figures for the largest known speci men. In 1990, or thereabouts, a fifty-footer had been killed off New Zealand, but this one was half as big again.
These thoughts flashed through his mind in an instant, and in that same moment he saw that the great beast was already maneuvering for the kill. It was heading for one of the calves, and ignoring the frantic mother. Whether this was cowardice or common sense there was no way of telling; perhaps such distinctions were meaningless to the shark's tiny and utterly alien mind.
There was only one thing to do. It might spoil his chance of a quick kill, but the calf's life was more important. He punched the button of the siren, and a brief, mechanical scream erupted into the water around him.
Shark and whales were equally terrified by the deafening shriek. The shark jerked round in an impossibly tight curve, and Don was nearly jolted out of his seat as the autopilot snapped the sub onto a new course. Twisting and turning with an agility equal to that of any other sea crea ture of its size, Sub 5 began to close in upon the shark, its electronic brain automatically following the sonar echo and thus leaving Don free to concentrate on his armament. He needed that freedom; the next operation was going to be difficult unless he could hold a steady course for at least fifteen seconds. At a pinch he could use his tiny rocket torps to make a kill; had he been alone and faced with a pack of orcas, he would certainly have done so. But that was messy and brutal, and there was a
neater way. He had always preferred the technique of the rapier to that of the hand grenade.
Now he was only fifty feet away, and closing rapidly. There might never be a better chance. He punched the launching stud.
From beneath the belly of the sub, something that looked like a sting ray hurtled forward. Don had checked the speed of his own craft; there was no need to come any closer now. The tiny, arrow-shaped hydrofoil, only a couple of feet across, could move far faster than his vessel and would close the gap in seconds. As it raced forward, it spun out the thin line of the control wire, like some underwater spider laying its thread. Along that wire passed the energy that powered the sting, and the signals that steered the missile to its goal. It responded so instantly to his orders that Don felt he was controlling some sensitive, high-spirited steed.
The shark saw the danger less than a second before impact. The resemblance of the sting to an ordinary ray confused it, as the designers had intended. Before the tiny brain could realize that no ray behaved like this, the missile had struck. The steel hypodermic, rammed forward by an exploding cartridge, drove through the shark's horny skin, and the great fish erupted in a frenzy of terror. Don backed rapidly away, for a blow from that tail would rattle him around like a pea in a can and might even damage the sub. There was nothing more for him to do, except to wait while the poison did its work.
The doomed killer was trying to arch its body so that it could snap at the poisoned dart. Don had now reeled the sting back into its slot amidships, pleased that he had been able to retrieve the missile undamaged. He watched with awe and a dispassionate pity as the great beast succumbed to its paralysis.
Its struggles were weakening. It was now swimming aimlessly back and