When he was eighteen, drunk in a field in Innsbruck, hitchhiking across Europe, Douglas Adams looked up at the sky filled with stars and thought, "Somebody ought to write the Hitchhiker's Guide to the Galaxy." Then he went to sleep and almost, but not quite, forgot all about it.
The Hitchhiker's Guide to the Galaxy is the trilogy-in-six-books by Adams, with the sixth book being written by Artemis Fowl's Eoin Colfer. It began in 1979, as an adaptation of the radio series of the same name, also written by Douglas Adams, but eventually diverged from and expanded on the plot of the original. It's arguably the best-known version of the series.
The first book, The Hitchhiker's Guide to the Galaxy, was adapted straight from the radio shows. It covers Arthur Dent's last day on Earth, meeting with the other characters, questing for the legendary planet of Magrathea, and the story of Deep Thought. It leads directly into the next book.
The second, The Restaurant at the End of the Universe, also came from the radio version, although with many more changes and a shifting-about of the order of events. These first two books can, in many ways, be thought of as halves of the same story, in a way that the sequels aren't. In Restaurant, the characters visit Milliways, the titular establishment at the rear end of time, Zaphod and Trillian attempt to discover who truly runs the universe, and Ford and Arthur end up on a spaceship full of useless people which crashes into prehistoric Earth.
The third book, Life, the Universe and Everything, is the most conventionally adventure-ish book of the series; not surprising, since it was adapted from an unused Doctor Who script. Ford and Arthur get pulled back to modern-day Earth, pre-explosion, where Slartbartifast enlists them and, eventually, the rest of the cast to stop the machinations of the xenophobic Krikkitmen, who, at the dawn of galactic civilization, were responsible for the bloodiest war the universe has ever seen, but who were sealed in a slow-time bubble... until now.
The fourth book, So Long, and Thanks for All the Fish, is, on the other hand, probably the most character-based of the series. Arthur returns to an unexpectedly-resurrected Earth, but after his adventures among the stars, he's just as out of his element here as he was when he first hitched a ride on a spaceship. He attempts to solve the mysterious disappearance of the planet's dolphin population alongside his new girlfriend, Fenchurch, who is implied to be the woman featured in the first pages of the first book.
The fifth, Mostly Harmless, is a dark romp through the corridors of probability. The Guide has been taken over by the Vogons, and Arthur has lost his love and has settled in as a sandwich-maker in a primitive tribe on a faraway planet. But then Trillian shows up with a surprise — a teenage daughter, conceived with Arthur's donated DNA. Its creator felt it was too strongly coloured by a bitter breakup he had undergone at the time, and intended to write a sequel, but due to his infamous procrastination, died before completing anything tangible.
A sixth book, And Another Thing... was written by Eoin Colfer, author of the Artemis Fowl children's novels, and published in October 2009. Starting where Mostly Harmless left off, the tone of the book in general is much lighter and removes the downer beginning the series ended with. There is some controversy as to whether it lives up to the main series, and it is considered non-canon by some fans.
For all versions of the story, including the TV Series, Radio Series, Video Game/Text Adventure, Film, Theatre Plays and Comic Series, see The Hitchhiker's Guide to the Galaxy.
The Hitchhiker's Guide to the Galaxy book series provides examples of the following tropes:
- Adaptational Villainy: The mice. In the original radio show they held no malice towards Arthur at all; on the contrary, they offered to pay him handsomely if he found the ultimate question for them. In the book, they want to cut up his brain to extract the question manually.
- Artifact Title: Lampshaded with Mostly Harmless bearing the description, "The fifth book in the increasingly inaccurately named Hitchhiker's Trilogy." Some later editions of the other novels include similar blurbs, and And Another Thing... is simply subtitled "Book 6 of 3".
- Backing into Danger: Parodied in the following passage:Arthur backed down the passageway, feeling increasingly nervous. After a while, he realized that this was because, in every horror movie he'd ever seen, when the hero backs slowly down a passageway, he winds up backing into a monster.At this point he spun round very suddenly, and saw nothing.He started backing down the passageway in the other direction. After a few moments, he realized that he was now backing toward whatever he had been backing away from in the first place.This, he could not help feeling, was a very foolish thing to do.
- Then he spins around again and winds up face-to-face with a monster.
- Evolutionary Stasis: It is mentioned that the Vogons stopped evolving shortly after they stopped being an aquatic species. The planet Vogsphere has created many other life forms far more appealing than the Vogons, which they inevitably destroy for their own amusement.
- To lampshade it, the book even states that evolution threw up its metaphorical hands in horror at the sight of the Vogons in daylight, refused to let them evolve again, and produced the other, amazingly beautiful creatures of Vogsphere in compensation for the Vogons.
- FTL Travel Sickness: The sensation of entering hyperspace is described as feeling like getting turned inside out at the navel. The experimental Infinite Improbability Drive has even more esoteric effects, such as temporarily turning the passengers into penguins.
- Happy Ending Override: Between ''So Long and Thanks For All the Fish" and "Mostly Harmless", Arthur's true love Fenchurch mysteriously disappears in-universe (it's implied that a hyperspace-travel accident caused Arthur to accidentally jump into a timeline where she never existed).
- Humans Are Not the Dominant Species: Humans are merely unknowing experimental test subjects being monitored and controlled by other-dimensional beings who assume the forms of white mice. A more profound question is how the dolphins got here and left, since they are also superior to us.
- In-Universe Factoid Failure:
- Ford Prefect chooses his name the name of a rather mediocre British car apparently on the assumption that cars were the dominant species on the planet. The movie adaptation extrapolates from this the scene of Ford and Arthur's first meeting, Arthur saving Ford from attempting to shake hands with a car (a Ford Prefect, naturally).
- The Cutaway Gag sequence about the Vl'Hurg-G'Gugvuntt fleet that attempted to invade the Earth, only to be accidentally swallowed by a small dog in its entirety "due to a terrible miscalculation of scale".
- It Runs on Nonsensoleum: The series' phlebotinum runs entirely on Rule of Funny. Among other things, we have the Infinite Improbability Drive, Bistromathics — a field of computations based on the non-absoluteness of the mathematics involved in restaurant dining — and the Somebody Else's Problem field, a cloaking device that weaponizes the Weirdness Censor by making something appear so ludicrously inconceivable that people just ignore it. There's also the species who built a starship powered by bad news, but nobody wanted it to show up.
- Lemony Narrator: A staple of Douglas Adams' work. The fictional guide itself is also written in this style.
- The Meaning of Life: A machine is fed information to calculate the ultimate answer to life, the universe and everything. The answer? 42. The machine can't calculate the ultimate question, but it can design another machine that might...
- PostWake-Up Realization: Varies from version to version where Arthur is sometimes like this about noticing that there are bulldozers ready to knock down the house he lives in.From the Book: "The word 'bulldozer' wandered through his mind for a moment, in search of something to connect with."
- Prophecy Armor: Arthur's encounter with Agrajag leaves him believing that he can't die until he's visited a planet called Stavromulos Beta, where he ducked to avoid being shot and the shot killed Agrajag instead. It turns out to actually be a nightclub on Earth called "Stavro Mueller's Beta".
- Space Sector: The sector of the Galaxy containing Earth is "Sector ZZ9 Plural Z Alpha"; like much else in the franchise, likely an Affectionate Parody of a widely-used science fiction trope.
- Trilogy Creep: "The increasingly inaccurately named Hitchhiker's trilogy."
- Unlucky Extra: Agrajag is an unfortunate soul that happens to reincarnate into incidental creatures that Arthur Dent accidentally kills (a pot of flowers, a fly, etc...). Agrajag eventually becomes aware of his past lives and becomes more and more spiteful toward Arthur until his dislike actually materializes into the "Cathedral of Hate", to which he eventually abducts Arthur; thanks to the vagaries of time travel, it turns out that he can't kill Arthur because one of the deaths he wants revenge for hasn't happened yet (it eventually occurs in the final chapter of Mostly Harmless). Arthur proceeds to accidentally kill him again while escaping.
- What Other Galaxies?: The Universe is mentioned several times (the Answer to Life, the Universe, and Everything, The Restaurant at the End of the Universe), yet no other galaxy is ever acknowledged. To be fair, the Restaurant at the End of the Universe is at the temporal end of the universe, not the physical end.