lying against the delicate saffron of the skin. Dr. Ku
Sui seemed resting in dreamless, unclouded sleep. But for only a
moment. Soon the eyelids quivered and slowly opened--and a great
change was immediately visible in the man's green eyes.

Many observers have recorded that under the veiled, enigmatic eyes of
Dr. Ku Sui there lurked a sultry glimmer of fire; or perhaps it was
that the observers who met these eyes always imagined the fire, being
conscious of the devil and the tiger in the man. But Carse and
Leithgow now saw that all that was gone.

No mask lay over the green eyes now, no spark of fire glinted deep in
them. They were clear and serene; they hid nothing; almost they were
the eyes of a fresh, innocent child. Dr. Ku Sui, he of a hundred
schemes, a score of plots, he of the magnificent capacity and untiring
brain bearing ever toward his goal of lordship of the solar system--it
was as if he had slipped into a magic pool whose waters had washed him
clean and given him innocence and eyes of peace....

* * * * *

The Eurasian breathed deeply, then smiled at the two men standing by
him.

"Now," whispered Eliot Leithgow. "Ask him anything. He will answer
truthfully."

The Hawk lost no time. He asked:

"Dr. Ku, you will perform the brain transplantations for us?"

"Yes, my friend."

The man's tone was different. Gone was the suaveness, the customary
polite mockery; it was frank, open, genuinely pleasant.

"Is it true, Dr. Ku, that your coordinated brains will die, if left in
their case?"

"Yes, they will die if left there."

"Within what time, to save them, must the operations to transplant
them into human bodies be started?"

"Within twenty-five, perhaps thirty, minutes at the most."

"Can all five brains be given the initial steps for transplantation
into the heads of your four white assistants and the coolie prisoner
within one hour--the remaining half of the two hours the brains said
they would retain the necessary vitality?"

Dr. Ku smiled at him. There was no malice in the thunderbolt that he
unleashed then. He simply told what he knew to be the truth.

"By fast work they could be, and so saved, although the subsequent
operations will take weeks. But the brains cannot be transplanted into
the heads of my four white assistants."

"What?" Both the Hawk and Leithgow cried the word out together. "They
cannot?"

* * * * *

Dr.