rrison," Cercy asked, "is Plan Three set up?"

"Sure."

"Give it a try."

While Harrison was making his last adjustments, Cercy watched Darrig.
The plump little physicist was staring thoughtfully into space,
muttering to himself. Cercy hoped he would come up with something. He
was expecting great things of Darrig.

Knowing the impossibility of working with great numbers of people,
Cercy had picked his staff with care. Quality was what he wanted.

With that in mind, he had chosen Harrison first. The stocky,
sour-faced engineer had a reputation for being able to build anything,
given half an idea of how it worked.

Cercy had selected Malley, the psychiatrist, because he wasn't sure
that killing the Ambassador was going to be a purely physical problem.

Darrig was a mathematical physicist, but his restless, curious mind
had come up with some interesting theories in other fields. He was the
only one of the four who was really interested in the Ambassador as an
intellectual problem.

"He's like Metal Old Man," Darrig said finally.

"What's that?"

"Haven't you ever heard the story of Metal Old Man? Well, he was a
monster covered with black metal armor. He was met by Monster-Slayer,
an Apache culture hero. Monster-Slayer, after many attempts, finally
killed Metal Old Man."

"How did he do it?"

"Shot him in the armpit. He didn't have any armor there."

"Fine," Cercy grinned. "Ask our Ambassador to raise his arm."

"All set!" Harrison called.

"Fine. Go."

In the Ambassador's room, an invisible spray of gamma rays silently
began to flood the room with deadly radiation.

But there was no Ambassador to receive them.

"That's enough," Cercy said, after a while. "That would kill a herd of
elephants."

But the Ambassador stayed invisible for five hours, until some of the
radioactivity had abated. Then he appeared again.

"I'm still waiting for that typewriter," he said.

* * * * *

"Here's the Analyzer's report." Malley handed Cercy a sheaf of papers.
"This is the final formulation, boiled down."

Cercy read it aloud: "The simplest defense against any and all
weapons, is to _become_ each particular weapon."

"Great," Harrison said. "What does it mean?"

"It means," Darrig explained, "that when we attack the Ambassador with
fire, he turns into fire. Shoot at him, and he turns into a
bullet--until the menace is gone, and then he changes back again." He
took the papers o