The Other Likeness — James H. Schmitz

"Why shouldn't we continue with the plan until . . ."

Kilby interrupted without change of expression.

"Until we hear some day that billions of human beings are dying on the Federation's worlds?"

Halder kept his eyes fixed on the traffic pattern ahead. "It won't come to that," he said.

"Won't it? How can you be sure?" Kilby asked tonelessly.

"Well," Halder asked, "what else can we do? You aren't suggesting that we give ourselves up --"

"I've thought of it."

"And be picked apart mentally and physically in the Federation's laboratories?" Halder shook his head. "In their eyes we'd be Kalechi's creatures . . . monsters. Even if we turn ourselves in, they'll think it's some trick, that we'd realized we'd get caught anyway. We couldn't expect much mercy."

But there "is" a limit to how perfect a counterfeit can be -- a limit that cannot be passed without an odd phenomenon setting in. . . .