Synopsis: Sime or Gen? Humanity had mutated into two branches: the Simes who must pray on the Gens to survive; the Gens whose bodily energies alone could feed the Simes. Laneff Farris had thought herself an in-between until the unforgettable day she changed over into Sime form - and in the energy hunger that overcame her kill the two who had tried to help her. When she finally overcame her murderous lust for life-energy, she dedicated herself to finding a way to reunite humanity. Through her biochemical researches, she believed she had found the answers. If her findings were right, it would mean the end of the world's division. But was the world itself ready for this? Extremists said no. And to prove it, the intrigued to have Laneff kill again - publicly. (adapted from the back cover of the DAW edition)