He knew his destination, too. He knew the two rooms thoroughly, having
explored them carefully and gone away undetected. And now that he knew
the one he sought was in those rooms, he was ready to make his final
investigation of the man.

He swam on through the utter blackness of the brackish water until his
head broke surface again. Then he went on along the great conduits that
were above the level of the sea.

* * * * *

Captain Davidson Greer sat in the gun tower that overlooked the
Officers' Barracks and the courtyard surrounding the five-story
building. He was a tall, solidly built man in his early thirties, with
dark gray-green eyes and dark blond hair. He didn't particularly care
for gun-tower duty, but this sort of thing couldn't be left to anyone
who was not in on the secret of the Nipe. As long as Colonel Mannheim
was here in Government City, there would be special officers guarding
him instead of the usual guard contingent.

Not that Captain Greer was actually expecting the Nipe to make any
attempt on the colonel's life; that was too remote to be worried about.
But the gun towers had been erected fifty or more years before because
there were always those who wanted to attempt assassination. Officers of
the World Police had not enjoyed great popularity during the
reconstruction period after the Holocaust. The petty potentates who had
set themselves up as autocratic rulers in various spots over the Earth
had quite often decided that the best way to get the WP off their backs
was to kill someone, and quite often that someone was a Police officer.
Disgruntled nationalists and fanatics of all kinds had tried at various
times to kill one officer or another. The protection was needed then.

Even now there were occasional assassins who attempted to invade World
Police Headquarters, but they were usually stopped long before they got
into the enclosure itself.

Still, there was always the chance. There had been, in the past few
years, an undercurrent of rebellion all over Earth because of the Nipe.
The monster hadn't been killed, and there were those who screamed that
the failure was due to the inefficiency of the Police.

One attempt had already been made on the life of a Major Thorensen
because he had failed to get the Nipe after a raid in Leopoldville. The
would-be assassin had been cut down just before he threw a grenade that
would have killed half a dozen men. Captain Greer ha