Arthur Dent is your normal human being, and so he naturally is more concerned about his house being knocked down than facing the fact that the world is about to end. His friend Ford Prefect, he comes to learn, is actually a researcher from a planet somewhere in the vicinity of Betelgeuse, but before he can even begin to comprehend this fact, he finds himself zipped up into the confines of the Vogon space cruiser that has just destroyed the planet Earth. Things become even trickier for him when he discovers the great usefulness of sticking a Babel fish into his ear and then meets the singular President of the Galaxy Zaphod Beeblebrox and his shipmate Trillian, both of whom Arthur actually met months before at a party. Such impossible coincidences are explained by the fact that Beeblebrox's ship is powered by the new Infinite Improbability Drive. Dent grows more and more confused during his travels on board the Heart of Gold, and the story eventually culminates with an amazing visit to an astronomically improbable world.
Much of the humor here is impossible to describe; this novel must be read to be appreciated. It seems like every single line holds a joke of some kind within it. The characters are also terrific: the unfortunate Arthur Dent, who basically has no idea what is going on; Ford Prefect, Arthur's remarkable friend from Betelgeuse; Zaphod Beeblebrox, with his two heads, three arms, and cavalier attitude; Trillian the lovely Earth girl who basically flies the Heart of Gold; Slartibartfast the planet builder and fjord-make extraordinaire; and my favorite character of all, Marvin the eternally depressed robot. Life-"loathe it or ignore it, you can't like it" is the Paranoid Android's philosophy. One brilliant thing that Adams does is to step away from the action every so often to present interesting facts about the universe as recorded in the Hitchhiker's Guide; here we learn about Vogon poetry, the Ravenous Bugblatter Beast of Traal, Trans Galactic Gargle Blasters, and other fascinating tidbits about life in the crazy universe Adams created. He even gives the reader the ultimate answer to the question of Life, the Universe, and Everything in these pages.
This novel is just an amazingly hilarious read that will leave you yearning for more; to our great fortune, Adams indeed left us more in the form of four subsequent books in the Hitchhiker's "trilogy." If you don't like science fiction, it doesn't matter; read this book just for the laughs. The most amazing thing about Adams' humor is the fact that everyone seems to "get" it. Adams broke all the rules in writing a novel quite unlike any that had come before it, and he succeeded in spades. This may well be the funniest novel ever written.