Douglas Adams’s The Hitchhiker’s Guide to the Galaxy first appeared in book form in 1979, after Adams originally conceived it as a radio play. The Hitchhiker’s Guide to the Galaxy explores and satirizes many facets of modern life, such as the legitimacy of authority, the absurdity of bureaucracy, and the search for the ultimate answer to the question of life, the universe, and everything. The book follows the galactic exploits of Arthur Dent, the last surviving Earthman, and Ford Prefect, originally of Betelgeuse, who escape the Earth immediately before its destruction at the hands of the Vogons. They meet up with Ford’s cousin and President of the Galaxy, Zaphod Beeblebrox, and his girlfriend, Trillian (also a former resident of Earth).

The Hitchhiker’s Guide to the Galaxy has enjoyed a long afterlife, spawning BBC television programs, a video game, a feature film, and numerous sequels. Adams himself penned an additional four books, while a sixth book in the series, composed by the writer Eoin Colfer, was published eight years after Adams’s death. Adams’s work has remained a milestone in modern science-fiction writing, inspiring other writers in the genre and maintaining a widespread readership. There are two asteroids named in commemoration of Adams and his work, streets and lecture series named in his honor, and “Towel Day” is still celebrated every May 25th, more than twenty years after Adams’s death.

All quotations in this guide come from the 1991 Longmeadow Press edition.

Content Warning: This guide contains some mild profanity and mentions of depression and death by suicide.

Plot Summary

Interspersed with entries from The Hitchhiker’s Guide to the Galaxy—the fictional creation of the author of The Hitchhiker’s Guide to the Galaxy—the book recounts the adventures of Arthur Dent, unlikely hero and last surviving Earthman, and Ford Prefect, an alien from Betelgeuse stranded on Earth for the past fifteen years. The book begins on a Thursday, as Arthur wakes up nursing a hangover. He sees yellow blurs outside his window and wonders why he drank too much at the pub the night before. It takes him a few moments to realize that the yellow blurs are bulldozers and that they have been sent to knock down his house. It is being demolished to make way for a new bypass.

Arthur runs outside and lies down in the pathway of the bulldozers, while a local official tries to reason with him. His friend, Ford Prefect, shows up at the scene and convinces Arthur to go with him to the pub. Ford knows something that Arthur does not: He need not worry about his home because the Earth itself is about to be demolished by the Vogons. These Galactic Civil Servants have been sent to clear the way for a hyperspatial bypass.

Ford manages to rescue Arthur and himself before the Earth is destroyed, hitching a ride on the Vogon ship. However, the Vogons are infamously unpleasant, and they despise hitchhikers. Ford lends Arthur his copy of the electronic book, The Hitchhiker’s Guide to the Galaxy, so that Arthur can understand what is going on. Unfortunately, they are discovered by the Vogons and forced to endure the captain’s reading of his poetry—the “third worst in the Universe” (45). They are then escorted to the airlock, where they are thrown into “the total vacuum of space” (53). While they only have about thirty seconds to live, a passing spaceship—the Heart of Gold, recently stolen by the President of the Galaxy, Zaphod Beeblebrox—picks them up. Marvin, a robot with depression, escorts the men to the bridge of the ship. Ford is shocked to see his cousin, Zaphod, at the helm.

Arthur claims to have met Zaphod back on Earth—though Zaphod, at that time, did not have the extra head and arm that he now has and was called “Phil” (73). Arthur alleges that Zaphod gatecrashed an Earth party, swooped in and went off with Arthur’s love interest, Trillian. Just then, Trillian walks onto the bridge. It appears as if “’this sort of thing [is] going to happen every time we use the Improbability Drive’” (74). The Infinite Improbability Drive powers the Heart of Gold, a form of miraculous transport that makes the building of hyperspatial bypasses moot. Thus, the destruction of Earth was utterly pointless.

Zaphod is on a mission to discover the legendary planet of Magrathea, once home to the designer planet industry. He is unclear about the reason for his mission; in fact, he discovers that he himself has severed certain parts of both of his brains in order to hide his motives from himself. After a narrow escape from some ancient nuclear warheads, the Heart of Gold successfully lands on Magrathea, the planet many believe was merely a myth. Zaphod, Ford, and Trillian go off to explore, while Arthur and Marvin are left to “guard” the ship. While the first three are quickly rendered unconscious by a gas released as they descend into the underground bunkers, Arthur stumbles upon an old man who takes him into the heart of Magrathea.

Slartibartfast, the old man, reveals some highly disturbing news: Earth is actually one of their designer planets, commissioned by a very intelligent species of pandimensional beings, disguised as mice. Earth was built as a kind of organic computing device, its purpose to calculate the question to life, the universe, and everything. As Arthur discovers, the answer—“forty-two” (120)—was enigmatic, so this species has their super-computer, Deep Thought, draw up the plans for an even more sophisticated computer to devise the question. This turns out to be the Earth.

Slartibartfast tells Arthur that the mice are quite excited to meet him, and they find the rest of the group to fill them in on the story of Earth. It was destroyed, unfortunately, “’five minutes before the program was completed’” (127). Thus, the mice have commissioned a new planet, Earth II, but with the discovery that Arthur was present on the planet just before its destruction, the mice determine that his brain likely holds the ultimate question. Arthur is unwilling to hand over his brain to the mice. Just as it looks as if he will have no choice, sirens blare and chaos ensues: The intergalactic police have caught up with Zaphod for stealing the Heart of Gold. He, Arthur, Ford, and Trillian escape the mice, only to be pursued by the cops who are shooting at them. Suddenly, the shooting ceases and all is quiet. It appears as if the cops’ life support systems have failed. In addition, Slartibartfast leaves his aircar behind. The four can escape back to the ship. They find Marvin in a heap, full of self-loathing. He has been talking to the police officers’ spacecraft, and the craft, which is responsible for the life support systems of the cops, has died by suicide.

The four humanoids and Marvin escape in the Heart of Gold, ready to embark on a whole new adventure—lunch. Zaphod directs the ship to head to the Restaurant at the End of the Universe, which will be the title of the second book in the series.