Solo smashed the giant down with a two-handed blow to the back of the neck. The giant rested on hands and knees, trying to rise. Solo kicked him on the point of the chin. The bull neck gave way with a loud, sickening snap, and Gotz collapsed.

While Solo had been struggling with the giant, Illya had disposed of his man with a single thrust to the throat. Mahyana had handled her man with a judo throw, hurling the startled sadist against a wall.

The attack had taken seconds, but already Marcus Fitzhugh was shouting. "Guards! Go in! You stupid fools! How can you escape? Guards!"

The door opened.

As if this were a signal they had been waiting for, Illya and Solo leaped to either side of the door. Their actions were quick, smooth, and automatic, with no need to have planned it with talk.

The guards ran in. Two guards armed with machine-pistols. Solo chopped one. Illya tripped the other, kicked him in the face as he tried to rise. Mahyana had the two guns. They were through the door just before it closed.

"The left corridor," Illya cried out.

Mahyana handed one machine-pistol to Solo.

Marcus Fitzhugh was shouting. "They are out! Blue alert!"

Alarms clanged.

"Where are we going?" Mahyana gasped.

"There is always an Achilles' heel," Illya said. "I know where it is."

Four guards appeared. Solo and Mahyana shot them down. The girl took a bullet that creased her shoulder, drawing quick blood. Illya had reached a door they had passed earlier.

The Russian tore at his belt-the belt they had left him when they took all they thought was a weapon. He tore off a piece of the belt, pulled a thread on the edge and shouted.

"Back, flat down!"

They fell to the floor. A shattering explosion shook the steel corridor. The door in front of them blew open with the force of the powerful explosive. The special belt was an explosive in itself, fused by the threads at the edge. The three agents were up and through the door.

Mahyana stared at the small, closet-like room that seemed totally empty. "There's nothing in here! What-?" she cried.

Illya smiled. The Russian pointed to a large box against the wall. Metal conduit went in and out of the box. Thick sheaves of conduit like bundles of spaghetti.

"The main circuit box, fuses and all. The place is all electric, and this is the Achilles' heel."

Illya Kuryakin took the rest of his belt, wrapped it over the metal box, and pulled the thread. He pushed Solo and Mahyana out into the corridor again.

Marcus Fitzhugh's voice hissed savagely. "There they are, Corridor 72, all."

The explosion seemed to burst their eardrums, shattering the steel walls, shaking the floor beneath them.

Then all was suddenly quiet.

Illya and Solo raised their heads.

The alarms had stopped. The voice on the loudspeaker had been cut off. The noise of air-conditioning machinery ceased. The underground complex was as silent as a tomb.

"And blind," Illya said. "All their power is off. Now they are deaf and blind, no better than we."

"Look!" Solo said.

All down the corridors doors stood open. Illya laughed.

"I expected that. The doors are spring loaded and open when the power is off."

"All the doors are open?" Mahyana said.

"I'm sure of it. Now, all we have to do is evade the guards. First we leave this corridor. Our position is reported. I don't imagine they have many guards, they would rely on their electronic devices in this wilderness."

They moved quickly and silently until they had put three other corridors between them and the point of the explosion. They had seen no one, but they could hear voices somewhere. Illya faced Mahyana.

"I think the main elevator shaft is straight ahead. It will be out of order, but there will be a cable to climb. They will expect us to break out. That is your job, Mehyana. Go up the cable, try to reach the surface."

"And you?" Mahyana said.

"We came here for a reason," Solo said. "We can't leave without trying to find out what PowerTen is."

"But." the girl said.

"No but, my dear," Illya said. "We have to try."

The brown-skinned girl nodded and turned without another word. She slung the machine-pistol over her shoulder, and entered the open door of the elevator shaft. Then she was gone.

"This way, I think, Napoleon," Illya said. "The sound of machinery has to be the manufacturing area and it is this way."

The two agents moved silently along the corridors. Twice they encountered pairs of armed guards. They killed them quickly and simply with bursts from the machine-pistols. They had five machine-pistols now.

At last they came to their goal. A great cavern was hollowed out beneath high steel walkways. Complex chemical equipment stood silent, motionless below. Men down there moved frantically trying to make repairs.

Illya located the office and laboratory. They shot down the three guards there. Solo laid all the machine-pistols on the floor beside the open door.

"Go ahead," Solo said. "I'll hold them off when they come. Mahyana will lead them off for a time, but they'll be back."

Solo lay on the floor, the machine-pistols ready. Illya began to search the office laboratory.

All was silent in the vast underground complex called The Belly.

Until the voice hissed, "I admire you, gentlemen. Perhaps you cold have escaped."

Marcus Fitzhugh stood in the room, a Luger in his hand. He stood there behind Solo, facing Illya. Behind him Herrara held Mahyana. There were two other guards behind them. They all stood before an opening in the office wall that had not been there.

"You see, Mr. Kuryakin, not all our little secrets were operated on the main power lines. I was aware of our weak spot. I prepared a small circuit of secret corridors on standby power. It seems I was wise. You will now please stand closer together, and do not attempt to reach those weapons."

Fitzhugh smiled again, his horrible burned face twisting with a certain admiration. His hissing voice spoke quietly.

"You will be killed at once, of course. But such devotion to duty deserves the reward of knowledge. You want to know about PowerTen? Very well, I will tell you.

THREE

Solo and Illya stood there and looked at each other as they heard the nature of PowerTen.

"So you see, it is really a very interesting substance. Once ingested it will raise any neurotic impulse to a power of ten-ten time the urge, the obsession, the drive of a normal neurosis. Think of it! I can see that Mr. Kuryakin understands the chemical data I have outlined, but for Mr. Solo and Miss Mahyana let me simplify. Like all alkaloids, say, marijuana or peyote, it induces a state of heightened hysteria. However, unlike anything else known, it has the effect of hypnosis—it can be directed. Under its influence, a man can be made to do what he is instructed, mindlessly and without fear or hesitation, provided the tendency was already there. For example, if some young man, obviously neurotic and disturbed by the power structure of our foolish world, is given PowerTen he will kill a political leader he only wanted to defy before he took the drug. You see the implications? All we have to do is locate young people with the neurotic desire to defy, steal, attack, rebel, destroy, give them PowerTen—and tell them to do what they desire. They will do it!"

Illya nodded slowly. "Happily, without remorse or hesitation. They will feel exhilarated."

"Precisely!" Marcus Fitzhugh said eagerly. "And certain subjects can even be directed to do specific acts, as you well know from our recent results with the African president, the gold theft, the laboratory fire, and the deputy chief."