In the early part of the Twenty Second Century, Dr. Richard Arcot,
hailed as "the greatest living physicist", and Robert Morey, his
brilliant mathematical assistant, discovered the so-called "molecular
motion drive", which utilized the random energy of heat to produce
useful motion.
John Fuller, designing engineer, helped the two men to build a ship
which used the drive in order to have a weapon to seek out and capture
the mysterious Air Pirate whose robberies were ruining Transcontinental
Airways.
The Pirate, Wade, was a brilliant but neurotic chemist who had
discovered, among other things, the secret of invisibility. Cured of his
instability by modern psychomedical techniques, he was hired by Arcot to
help build an interplanetary vessel to go to Venus.
The Venusians proved to be a humanoid race of people who used telepathy
for communication. Although they were similar to Earthmen, their blue
blood and double thumbs made them enough different to have caused
distrust and racial friction, had not both planets been drawn together
in a common bond of defense by the passing of the Black Star.
The Black Star, Nigra, was a dead, burned-out sun surrounded by a
planetary system very much like our own. But these people had been
forced to use their science to produce enough heat and light to stay
alive in the cold, black depths of interstellar space. There was nothing
evil or menacing in their attack on the Solar System; they simply wanted
a star that gave off light and heat. So they attacked, not realizing
that they were attacking beings equal in intelligence to themselves.
They were at another disadvantage, too. The Nigrans had spent long
millennia fighting their environment and had had no time to fight among
themselves, so they knew nothing of how to wage a war. The Earthmen and
Venusians knew only too well, since they had a long history of war on
each planet.