"Nomad" by George O. Smith is a science fiction novel first published in 1950. Guy Maynard is rescued from Martian captivity by inhabitants of Ertene, an invisible wandering planet. Armed with knowledge from this mysterious world, he launches invasions, becomes a hero, then faces court-martial. Fleeing between worlds while impersonating rulers and raising armies, Maynard's journey culminates in a dramatic bid for ultimate power across the Solar System. (This is an automatically generated summary.)