This book narrates the departure of a group of misfits from Earth to a voluntary exile in a world six million years back in time. A world that was believed to be virgin and wild, but is found to be dominated by two extraterrestrial races: Tanu, the creators of a knightly, medieval, slave society, and Firvulag dwarves who live in the forests. Both rival races have important psychic powers ... and humans do not waste time in joining one or the other side in a struggle for power.