"Thena's Boy" is book three of The Sol Chronicles and it is the story of Mart. Mart is the young Prince of the Martian people who were sent into exile by the Venetian, Rand. The Mortans had become Martians but they were not the first. The true Martians were their four-legged companions who developed deep bonds with the humans and their fierce warrior cousins. A split occurred long ago between the two true branches and the friendly true Martians kept the humans safely away from their cousins. Nothing had changed for the humans since their arrival on Mars. They continued to eke out an existence similar to what they had done on their arrival. Mart and his two cousins, Will and Robb, were determined to change that. With the help of their Martian companions - they succeeded.
Their success would serve to set the stage for all that would come to the rest of Sol's planetary system. They could not know the future consequences.