The Kur race once had a planet of its own, but somehow it was rendered unviable, either destroyed or desolate, apparently by the Kurs’ own hands. So they searched for a new home and found not one but two suitable planets—planets they set their minds to conquering. But these planets, Earth and its sister planet Gor, the Counter-Earth, were not undefended. The Kur attempted their conquest four times, only to be beaten back by the mysterious Priest-Kings, rulers of Gor. As the Kurii lurk deep within an asteroid belt, awaiting the chance to seize their prize, their attention is drawn to a human, Tarl Cabot. Tarl was once an agent of Priest-Kings but is now their prisoner, held captive in a secret prison facility. But what is their interest in Tarl Cabot?