etend to do it to me? I don't want to grow old any
more than they do!"

"But I wasn't pretending. Quiet, now, and let me think."

He waited until the watchguard had passed by the door, then raised his
head.

"Look here, Leah. Evidently the infection didn't take. This is what must
have happened. That treatment I gave you ten years ago must have made
you permanently immune to Blue Martian, and the antibodies it formed in
your cells simply protected you against this new invasion of the virus.
It never occurred to me that the immunity would last so long. But don't
worry, I'll find a way."

She looked suspicious. "What do you mean?"

"I mean that there's no reason why Blue Martian should be the only
vehicle for giving you the SDE. There must be other viruses that will
work equally well. It's only a question of finding one."

"And how long will that take you?"

"How long does anything take in Research? Maybe a week, maybe a year."

"And maybe ten! I can't wait, Dr. Wong. I'm thirty-five now; I'm growing
older. What good will a long life do me, if it only preserves me as the
middle-aged woman I'll be by then? And all those years that I'll be
getting older and older, there'll be Tanya, lively and pretty, to remind
me that I was once like that, too. I can't face it!"

"The watchguard will hear you!" Haggard-faced, he watched her shaking
shoulders, hearing her muffled sobs.

"You're a criminal, Dr. Wong! It was a crime, what you did to Tanya and
me."

"I didn't realize in the beginning or I'd never have touched the thing.
I know it now, even better than you do, but what can I do?"

She looked up and wiped her eyes, her mouth set hard. "I know what I can
do. I can report you to the Leader."

"What good will that do? You know how terrible you feel now about being
left out--though I swear I never meant it to be like this. But just try
to imagine. If you report me so that Leader Marley gets the secret of
SDE, then thousands of people will be put in just the same situation you
are in. You're only one person suffering. But then there'd be hundreds
of thousands, millions! Surely you wouldn't want to have that on your
conscience?"

"Do you think I'd care?"

"You would when you felt calmer. You're wrought up, ill. Let me send you
home. Promise me you'll go home quietly, talk it over with Tanya, and
not say anything to anyone else. I'll think of a way out for you. Just
be patient."

"Patient!"

He thought of calling