Sanctuary in the Sky / the Secret Martians

SANCTUARY IN THE SKY: A cold war among the stars was growing hotter by the minute. As Pag and Cathrodyne struggled for domination, a hot war threatened which would rend and annihilate whole planetary systems. The two master races would have consumed one another long ago, but for one single factor: Waystation. It was a stupendous synthetic world, famed throughout the galaxy. For Waystation was controlled by a neutral people, and until the greater powers could seize this strategic wonder planet and ferret out its secrets, they were doomed to fretful inactivity. But as a Cathrodyne vessel drew near to Waystation, the all-important balance of power stood in sudden peril. The ship in itself was routine. But on board was a stranger, a man of undiscovered race, who spoke too little, and , it appeared, knew too much . . . THE
SECRET MARTIANS: Jery Delvin had a most unusual talent. He could detect flaws in any scheme almost on sight -- even where they had eluded the best brains in the ad agency where he worked. So when the Chief of World Security told him that he had been selected as the answer to the Solar System's greatest mystery, Jery assumed that it was because of his mental agility. But when he got to Mars to find out why fifteen boys had vanished from a spaceship in mid-space, he found out that even his quick mind needed time to pierce the maze of out-of-this-world double-dealing. For Jery had become a walking bomb, and when he set himself off, it would be the end of the whole puzzle of THE SECRET MARTIANS -- with Jery as the first to go!