Dragon Dance

At the start of Christopher's Fireball trilogy, cousins Brad and Simon were thrown into an alternate world where the Roman Empire still held sway. From England they journeyed to and across a primitive America of Algonquins and Aztecs. This concluding volume (the first two were Fireball and New Found Land finds the boys staying with a California tribe, from which they are captured and brought to China. There they are befriended by the lonely teenage Emperor, but palace intrigue soon sends them away to the mountain religious retreat of Bei-Kun, a sect with unusual mental abilities. While grappling with this new discipline and their own beliefs, they unthinkingly propose mechanical concepts that help overthrow the Emperor. This is vintage Christopher; he introduces provocative ideas and their practical consequences in the course of a lively, colorful adventure. (10-14)