Humanity has united under an oppressive theocracy, and is spreading through the galaxy, leaving death, destruction and misery in its path. Alien races are invaded, conquered and either converted, or exterminated. Steve Cook, a gifted linguist who hates how his race is treating the aliens, is forced to serve aboard a human military craft as they start their attack on their latest victims, a marsupial race humans call Chipmunks. The Chipmunks, their true species named the Pileeta, are a race of gentle and intelligent beings. They embrace the principles of science, and are unable to believe in any version of God without hard scientific proof. They see humanity's spread across the galaxy as a plague, and fight desperately to save their own race from the "Zealot" humans. One Pileeta, a young scientist called Vilosa, discovers the only hope her race has to defeat the Zealots. To defeat these aggressive aliens, the Pileeta must annihilate the Zealots when they are far weaker, in their past. The plans of both humanity and Pileeta are thrown awry when Steve Cook and Vilosa are thrust together, thousands of years in the past. Can these two beings bring their races peacefully together, or will there be one final battle that dictates the survival of one race over the other.