The Hitchhiker's Guide to the Galaxy | Study Guide

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Course Hero. "The Hitchhiker's Guide to the Galaxy Study Guide." Course Hero. 28 Nov. 2016. Web. 15 June 2021. <>.

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Course Hero. (2016, November 28). The Hitchhiker's Guide to the Galaxy Study Guide. In Course Hero. Retrieved June 15, 2021, from

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Course Hero. "The Hitchhiker's Guide to the Galaxy Study Guide." November 28, 2016. Accessed June 15, 2021.


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The Hitchhiker's Guide to the Galaxy | Chapter 20 | Summary



Zaphod Beeblebrox, Trillian, Ford Prefect, Arthur Dent, and Marvin make their way across the dull gray, dull brown land. Out of the corner of her eye, Trillian thinks she sees movement off near the ship, but when she turns, nothing is there. She has no time to think about it. Zaphod has found a crater with an entrance to the planet interior. It is a break in the crust caused by the impact of something huge, wet, and rubbery—the exploded carcass of the lonely sperm whale. While Zaphod, Trillian, and Ford go in, Arthur remains outside with Marvin to stand guard. Soon the robot shuts himself off, and Arthur is left on his own.

As the other three make their way through the tunnels of Magrathea, Zaphod tries to explain to Ford why he stole the Heart of Gold: He stole it to look for a lot of things, but he doesn't know what. He thinks maybe if he knew, he wouldn't be able to look for them. This kind of thing happens regularly, though he doesn't know why—he gets an idea and just has to follow it through. Strangely, things always work out, no matter how poorly planned. He then tells Ford that he had recently become suspicious that there was something wrong with his mind. Just the night before, he had used specialized devices in the medical lab to examine his two heads and discovered that someone had modified both brains. In the middle of each brain was a section cut off from the rest. They communicated internally with each other, but with nothing else around them. Why is a mystery, but who is not. That person has left his initials burned into the sections: Z.B.

At that moment, a steel shutter behind the three explorers slams shut, and the chamber they are in begins to fill with gas.


Adams has created a cliffhanger, splitting up the group, abandoning Arthur Dent and Marvin on the planet surface, and leaving Zaphod Beeblebrox, Trillian, and Ford Prefect trapped in a chamber, filling with gas. Events and revelations in this chapter raise more questions to be answered in later chapters. What moved near the ship that Trillian almost saw out of the corner of her eye? What else beside Magrathea is Zaphod being driven to look for, and why? Why has he been altering his own brains and then hiding it from himself? And of course, why are the three being gassed? The only question that has been answered is what happened to the unfortunate whale.

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