y like a tin can, torn apart by mighty explosions,
its first floors visible from the air. Men and cars were pouring down
into it, fighting with the guards swarming to the surface.

* * * * *

Dixon watched intently. Sherikov's men were bringing up heavy guns,
big robot artillery. But the police ships were diving again.
Sherikov's defensive patrols had been cleaned from the sky. The police
ships whined down, arcing over the exposed laboratory. Small bombs
fell, whistling down, pin-pointing the artillery rising to the surface
on the remaining lift stages.

Abruptly Dixon's vidscreen clicked. Dixon turned toward it.

Reinhart's features formed. "Call off the attack." His uniform was
torn. A deep bloody gash crossed his cheek. He grinned sourly at
Dixon, pushing his tangled hair back out of his face. "Quite a fight."

"Sherikov--"

"He's called off his guards. We've agreed to a truce. It's all over.
No more needed." Reinhart gasped for breath, wiping grime and sweat
from his neck. "Land your ship and come down here at once."

"The variable man?"

"That comes next," Reinhart said grimly. He adjusted his gun tube. "I
want you down here, for that part. I want you to be in on the kill."

Reinhart turned away from the vidscreen. In the corner of the room
Sherikov stood silently, saying frothing. "Well?" Reinhart barked.
"Where is he? Where will I find him?"

Sherikov licked his lips nervously, glancing up at Reinhart.
"Commissioner, are you sure--"

"The attack has been called off. Your labs are safe. So is your life.
Now it's your turn to come through." Reinhart gripped his gun, moving
toward Sherikov. "_Where is he?_"

For a moment Sherikov hesitated. Then slowly his huge body sagged,
defeated. He shook his head wearily. "All right. I'll show you where
he is." His voice was hardly audible, a dry whisper. "Down this way.
Come on."

Reinhart followed Sherikov out of the room, into the corridor. Police
and guards were working rapidly, clearing the debris and ruins away,
putting out the hydrogen fires that burned everywhere. "No tricks,
Sherikov."

"No tricks." Sherikov nodded resignedly. "Thomas Cole is by himself.
In a wing lab off the main rooms."

"Cole?"

"The variable man. That's his name." The Pole turned his massive head
a little. "He has a name."

Reinhart waved his gun. "Hurry up. I don't want anything to go wrong.
This is the part I came for."

"You must remember s