In the 25th Century mankind fought against the hated telepathic slan race in the fierce slan-wars. The result was the extermination of almost all slans, and the establishment of a world-wide police state. Now in the 30th Century, slan Jommy Cross has escaped extermination and is now living in the world of cruel humans. Jommy was determined to avoid detection, track down other surviving slans and with them, solve the mystery of the slan's strange existence and superiority.