The book is insanely good. Podkayne is a girl from Mars, and she gets to go on a round trip to Venus and Earth with her annoying, coniving, greedy genius brother, and her kind politician great uncle. Of course they never make it to Earth because of an adventure on Venus! It teaches readers the importance of family (to me that is. Heinlein descirbes Venus in such great detail, making it seem like a future Las Vegas. Its a good read for all sci-fi lovers.