Or what it is like to love on an atom -- as experienced by Learoy Spofforth whose brother, Charles, inadvertently transfer him into the body of Kastrove an inhabitant of Kilson. There he is able to use his human memory to win Issa for himself, escape the slavery of their rulers and ally himself with the scientist group and helps destroy the conquering race. His return to his natural life deranges his mind but Charles and Learoy's wife hope to bring him back to normal. As an exercise in imagination, this is better than the usual Superman type of fiction.