Tom Sawyer, Huck Finn and Jim go to look over an inventor's experimental airship and end up accidentally stowed away on it when the professor takes off. He is not a stable man, and when he goes overboard in a storm the three of them are left in sole possession of a balloon they barely understand, drifting east across the Atlantic.
What follows is the Sahara, and then Egypt: lions, sandstorms, a caravan of robbers, the Pyramids and the Sphinx, and one errand back to Missouri for a corn-cob pipe. Tom insists on lecturing the other two on the geography and history of everything they pass, and Huck and Jim argue him to a standstill about most of it.
Mark Twain's 1894 sequel to Adventures of Huckleberry Finn is narrated again in Huck's voice, but trades the Mississippi and the social critique for a shorter comic travel tale built on bickering and tall-tale exaggeration.