n in and out on his liaison duties from the first."

"He had to go through those search points every time," Kelgarries
protested. "Thought nothing could get through those." The colonel
brightened. "Maybe he got his snooper films and then couldn't take them
off base. Have his quarters been turned out?"

Waldour's lips lifted in a grimace of exasperation. "Please, Colonel,"
he said wearily, "this is not a kindergarten exercise. In confirmation
of his success, listen...." He touched a button on his desk and out of
the air came the emotionless chant of a newscaster.

"Fears for the safety of Lassiter Camdon, space expediter for the
Western Conference Space Council, have been confirmed by the discovery
of burned wreckage in the mountains. Mr. Camdon was returning from a
mission to the Star Laboratory when his plane lost contact with Ragnor
Field. Reports of a storm in that vicinity immediately raised concern--"
Waldour snapped off the voice.

"True--or a cover for his escape?" Kelgarries wondered aloud.

"Could be either. They may have deliberately written him off when they
had all they wanted," Waldour acknowledged. "But to get back to our
troubles--Dr. Ruthven is right to assume the worst. I believe we can
only insure the recovery of our project by thinking that these tapes
were snooped anywhere from eighteen months ago to last week. And we must
work accordingly!"

There was silence in the room as they all considered that. Ashe slipped
down in his chair, his thoughts enmeshed in memories. First there had
been Operation Retrograde, when specially trained "time agents" had
shuttled back and forth in history, striving to locate and track down
the mysterious source of alien knowledge which the eastern Communistic
nations had suddenly begun to use.

Ashe himself and a younger partner, Ross Murdock, had been part of the
final action which had solved the mystery, having traced that source of
knowledge not to an earlier and forgotten Terran civilization but to
wrecked spaceships from an eon-old galactic empire--an empire which had
flourished when glacial ice covered most of Europe and northern America
and Terrans were cave-dwelling primitives. Murdock, trapped by the Reds
in one of those wrecked ships, had inadvertently summoned its original
owners, who had descended to trace--through the Russian time
stations--the looters of their wrecks, destroying the whole Red
time-travel system.

But the aliens had not chanced on the