The Hitchhiker's Guide to the Galaxy details the adventures of Arthur Dent, an Earthman from England, and Ford Prefect, an alien from a planet near Betelgeuse, as they flee the destruction of Earth. They are eventually picked up by smooth talking Zaphod Beeblebrox, the president of the galaxy, who is fleeing authorities with his girlfriend, Trillian, onboard the stolen spacecraft Heart of Gold. Also onboard the Heart of Gold is fan-favorite Marvin, a manically depressed robot who always has something to complain about. The group goes in search of the planet Magrathea, the planet of legend rumored to have riches beyond their wildest imaginings. They don't find the riches of legend, however. Instead, Arthur discovers the answer to the ultimate, universal, philosophical question, as well as finding his role in the bigger picture.
The Hitchhiker's Guide is a wonderfully funny book, interwoven with more sub-plot than any summary could reasonably deal with. Douglas satirizes many aspects of life normally taken for granted, and also questions the true importance of things in the big picture. For example, the aforementioned destruction of Earth takes place simply because someone wants to build a galactic highway. Mainly, though, the book is a lighthearted comedy in which nothing is taken seriously. You'll find few true heroes or villains in this book, and you'll see little of great deeds. Instead you find people, simply trying to get through life, and maybe make a quick buck along the way.