Podkayne Of Mars Author:Robert A. Heinlein The story is about Podkayne and her younger brother Clark accompanying their Uncle Tom on a trip to Venus and then to Earth (the trip never gets past Venus). There's a lot more here than meets the eye, because Tom is actually on a secret diplomatic mission to the upcoming Three Planets conference, and Poddy and Clark are along just to provide co... more »ver.
At first everything seems to be perfectly innocent, but then a stranger gets Clark to smuggle a package on board the spaceliner. Clark is a lot smarter than the stranger gives him credit for; the kid figures out that he's been given an atomic bomb that's been set to go off shortly after they leave Mars. Clark, being a boy genius, finds a way to defuse it. The plot gets thicker from there -- for the most part the story seems like an innocent travelogue of the future, but here and there the reader gets intimations of skulduggery afoot. By the end of the book, the plot has thickened to a perfect and satisfying consistency.« less